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REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

<strong>TIME</strong><br />

&<br />

<strong>DISTANCE</strong><br />

1


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

MODULE OBJECTIVE:<br />

Decision making for planning, policy, and management relies increasingly on<br />

quantitative reasoning, which entails the collection, analysis and interpretation of<br />

quantitative data. This course is designed to introduce principles and techniques to solve<br />

time and distance related problems.<br />

Develop Logical Reasoning in a Problem-Solving Framework. One goal is to<br />

develop a disciplined logical analysis of “word” problems. Such reasoning is the<br />

foundation for building simple mathematical models of problems – models implicit in<br />

counting time and distance. A good way to learn this logical thinking is by working many<br />

exercises. Students will use this reasoning often (consciously or unconsciously) in<br />

computer science, operations research, and probability and statistics. However, a logical<br />

mind will serve a person well in ANY field.<br />

At the end of these course students:<br />

• To be understood the types of formulae are used to measure time and Distance.<br />

• To be able to calculate time and distance while an object that moves at a constant<br />

rate is said to be in uniform motion, Uniform motion problems may involve<br />

objects going the same direction, opposite directions, or round trips.<br />

• To be solving many problems related to time and distance and which can be useful<br />

to students to face interviews.<br />

C. PREREQUISITIES (Important Formulas):<br />

SITAMS<br />

i) Speed = Distance/Time<br />

ii) Time = Distance/speed<br />

iii) Distance = speed*time<br />

iv) 1km/hr = 5/18 m/s<br />

v) 1 m/s = 18/5 Km/hr<br />

vi) If the ratio of the speed of A and B is a:b,then the ratio of the time<br />

taken by them to cover the same distance is 1/a : 1/b or b:a<br />

vii) suppose a man covers a distance at x kmph and an equal distance at y<br />

kmph.then the average speed during the whole journey is (2xy/x+y) kmph<br />

viii) An object that moves at a constant rate is said to be in uniform motion. The<br />

formula d = rt gives the relationship between distance d, rate r, and time t.<br />

Uniform motion problems may involve objects going the same direction,<br />

opposite directions, or round trips.<br />

2


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

D. Solved Examples:<br />

1.) Walking at the rate of 4kmph a man cover certain distance in 2hr 45 min. Running at a<br />

speed of 16.5 kmph the man will cover the same distance in.<br />

A. 12 min B. 25 min C. 40min D. 60 min<br />

Answer: Option C<br />

Explanation: Distance = Speed * time<br />

4*11/4 = 11km<br />

New Speed = 16.5 kmph<br />

Therefore time = D/S = 11/16.5 = 40min<br />

2.) A train covers a distance in 50 min, if it runs at a speed of 48kmph on an average. The<br />

speed at which the train must run to reduce the time of journey to 40min will be.<br />

A. 45 min B. 60 min C. 75 min D. None of these<br />

Answer: Option B<br />

Explanation: Time = 50/60 hr = 5/6hr<br />

Speed = 48mph<br />

distance = S*T = 48 * 5/6 = 40km<br />

time = 40/60hr = 2/3hr<br />

New speed = 40* 3/2 kmph = 60kmph<br />

3.) Two boys starting from the same place walk at a rate of 5kmph and 5.5kmph<br />

respectively. What time will they take to be 8.5km apart, if they walk in the same<br />

direction?<br />

A. 17 hrs B. 25 hrs C. 31 hrs D. 45 hrs<br />

Answer: Option A<br />

Explanation:<br />

SITAMS<br />

The relative speed of the boys = 5.5kmph – 5kmph<br />

= 0.5 kmph<br />

Distance between them is 8.5 km<br />

Time= 8.5km / 0.5 kmph = 17 hrs<br />

4.) Excluding stoppages, the speed of a bus is 54 kmph and including stoppages, it is 45<br />

kmph. For how many minutes does the bus stop per hour?<br />

A. 4 B. 6 C. 8 D. None of these<br />

Answer: Option D<br />

Explanation:<br />

Due to stoppages, it covers 9 km less.<br />

Time taken to cover 9 km = (9/54 x 60) min = 10 min.<br />

3


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

5.) 2 trains starting at the same time from 2 stations 200km apart and going in opposite<br />

direction cross each other at a distance of 110km from one of the stations. What is the<br />

ratio of their speeds?<br />

A. 7:3 B. 11:9 C. 18:4 D. None of these<br />

Answer: Option B<br />

Explanation:<br />

SITAMS<br />

In same time, they cover 110km & 90 km respectively<br />

so ratio of their speed =110: 90 = 11: 9<br />

6.) In covering a distance of 30 km, Sachin takes 2 hours more than Rohit. If Sachin<br />

doubles his speed, then he would take 1 hour less than Rohit. Sachin speed is:<br />

A. 5 kmph B. 16 kmph C. 21 kmph D. None of these<br />

Answer: Option A<br />

Explanation:<br />

Let Sachin’s speed be X km/hr.<br />

Then, 30/x - 30/2x = 3<br />

6x = 30<br />

x = 5 km/hr.<br />

7.) A train 140m long running at 60kmph. In how much time will it pass a platform 260m<br />

long?<br />

A. 5 kmph B. 16 kmph C. 21 kmph D. None of these<br />

Answer: Option A<br />

Explanation:<br />

Distance travelled = 140 + 260m = 400m,<br />

Speed = 60 * 5/8 = 50/3m<br />

Time = 400 * 3/50 = 24 Seconds<br />

8.) The ratio between the speeds of two trains is 7: 8. If the second train runs 440 kms in 4<br />

hours, then the speed of the first train is:<br />

A. 47.4 km/hr B. 57.19 km/hr C. 68.13 km/hr D. None of these<br />

Answer: Option D<br />

Explanation:<br />

Let the speed of two trains be 7x and 8x km/hr.<br />

Then, 8x = (440/4) = 110<br />

x = (110/8) = 13.75<br />

Speed of first train = (7 x 13.75) km/hr = 96.25 km/hr.<br />

4


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

9.) Sachin can cover a distance in 1hr 24min by covering 2/3 of the distance at 4 kmph<br />

and the rest at 5kmph.the total distance is?<br />

A. 5km B. 6km C. 7km D. 8km<br />

Answer: Option D<br />

Explanation:<br />

SITAMS<br />

Distance = 2/3S<br />

distance=1-2/3S=1/3S<br />

21/15 hr=2/3 S/4 + 1/3s /5<br />

84=14/3S * 3<br />

S= 6km<br />

10.) A person walks at 5kmph for 6hr and at 4kmph for 12hr.The average speed is.<br />

A. 4 1/3 B. 7 2/3 C. 9 ½ km D. 8km<br />

Answer: Option D<br />

Explanation:<br />

Avg speed = total distance/total time<br />

= 5*6 + 4*12 / 18<br />

=4 1/3 mph<br />

11)A person covers a certain distance at 7kmph .How many meters does he cover in<br />

2 minutes.<br />

A) 14 kmph B) 7 kmph C) 2400m D) 1200m<br />

Answer: Option C<br />

Explanation:<br />

Speed=72kmph=72*5/18 = 20m/s<br />

Distance covered in 2min =20*2*60 = 2400m<br />

12)If a man runs at 3m/s. How many km does he run in 1hr 40min<br />

A) 18 km B) 7 km C) 12 km D) 17 km<br />

Answer: Option A<br />

Explanation:<br />

Speed of the man = 3*18/5 kmph = 54/5kmph<br />

Distance covered in 5/3 hrs=54/5*5/3 = 18km<br />

13)A train covers a distance in 50 min ,if it runs at a speed of 48kmph on an average.The<br />

speed at which the train must run to reduce the time of journey to 40min will be.<br />

A) 18 kmph B) 60 km ph C) 30 kmph D) 50 kmph<br />

Answer: Option B<br />

5


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

Explanation:<br />

SITAMS<br />

Time=50/60 hr=5/6hr<br />

Speed=48mph<br />

distance=S*T=48*5/6=40km<br />

time=40/60hr=2/3hr<br />

New speed = 40* 3/2 kmph= 60kmph<br />

14)Vikas can cover a distance in 1hr 24min by covering 2/3 of the distance at 4 kmph and<br />

the rest at 5kmph.the total distance is?<br />

A) 18 km B) 6 km C) 12 km D) 17 km<br />

Answer: Option B<br />

Explanation:<br />

Let total distance be S<br />

total time=1hr24min<br />

A to T :: speed=4kmph<br />

diistance=2/3S<br />

T to S :: speed=5km<br />

distance=1-2/3S=1/3S<br />

21/15 hr=2/3 S/4 + 1/3s /5<br />

84=14/3S*3<br />

S=84*3/14*3 = 6km<br />

15)walking at ¾ of his usual speed ,a man is late by 2 ½ hr.<br />

the usual time is.<br />

A) 4 B) 7 ½ C) 7 D) 5<br />

Answer: Option B<br />

Explanation:<br />

Usual speed = S<br />

Usual time = T<br />

Distance = D<br />

New Speed is ¾ S<br />

New time is 4/3 T<br />

4/3 T – T = 5/2<br />

T=15/2 = 7 ½<br />

6


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

E. EXERCISE PROBLEMS:<br />

1)A man covers a distance on scooter .had he moved 3kmph faster he would have taken<br />

40 min less. If he had moved 2kmph slower he would have taken 40min more.the<br />

distance is.<br />

Solution::<br />

SITAMS<br />

Let distance = x m<br />

Usual rate = y kmph<br />

x/y – x/y+3 = 40/60 hr<br />

2y(y+3) = 9x ————–1<br />

x/y-2 – x/y = 40/60 hr y(y-2) = 3x —————–2<br />

divide 1 & 2 equations<br />

by solving we get x = 40<br />

2)Excluding stoppages, the speed of the bus is 54kmph and including stoppages, it is<br />

45kmph.for how many min does the bus stop per hr.<br />

Solution::<br />

Due to stoppages,it covers 9km less.<br />

time taken to cover 9 km is [9/54 *60] min = 10min<br />

3)Two boys starting from the same place walk at a rate of 5kmph and 5.5kmph<br />

respectively. what time will they take to be 8.5km apart, if they walk in the same<br />

direction.<br />

Solution::<br />

The relative speed of the boys = 5.5kmph – 5kmph = 0.5 kmph<br />

Distance between them is 8.5 km<br />

Time= 8.5km / 0.5 kmph = 17 hrs<br />

4)2 trains starting at the same time from 2 stations 200km apart and going in opposite<br />

direction cross each other at a distance of 110km from one of the stations. what is the<br />

ratio of their speeds.<br />

Solution::<br />

In same time ,they cover 110km & 90 km respectively<br />

so ratio of their speed =110:90 = 11:9<br />

7


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

5)Two trains start from A & B and travel towards each other at speed of 50kmph and<br />

60kmph resp. At the time of the meeting the second train has traveled 120km more than<br />

the first.the distance between them.<br />

Solution::<br />

SITAMS<br />

Let the distance traveled by the first train be x km<br />

then distance covered by the second train is x + 120km<br />

x/50 = x+120 / 60<br />

x= 600<br />

so the distance between A & B is x + x + 120 = 1320 km<br />

6)A thief steals a ca r at 2.30pm and drives it at 60kmph. The theft is discovered at 3pm<br />

and the owner sets off in another car at 75kmph when will he overtake the thief<br />

Solution::<br />

Let the thief is overtaken x hrs after 2.30pm<br />

distance covered by the thief in x hrs = distance covered by<br />

the owner in x-1/2 hr<br />

60x = 75 ( x- ½)<br />

x= 5/2 hr<br />

thief is overtaken at 2.30 pm + 2 ½ hr = 5 pm<br />

7) In covering distance, the speed of A & B are in the ratio of 3:4.A takes 30min more<br />

than B to reach the destination. The time taken by A to reach the destination is.<br />

Solution::<br />

Ratio of speed = 3:4<br />

Ratio of time = 4:3<br />

let A takes 4x hrs,B takes 3x hrs<br />

then 4x-3x = 30/60 hr<br />

x = ½ hr<br />

Time taken by A to reach the destination is 4x = 4 * ½ = 2 hr<br />

8)A person covers a certain distance at 7kmph .How many meters does he cover in 2<br />

minutes.<br />

Solution::<br />

speed=72kmph=72*5/18 = 20m/s<br />

distance covered in 2min =20*2*60 = 2400m<br />

8


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

9)If a man runs at 3m/s. How many km does he run in 1hr 40 min<br />

Solution::<br />

SITAMS<br />

speed of the man = 3*18/5 kmph = 54/5kmph<br />

Distance covered in 5/3 hrs=54/5*5/3 = 18km<br />

10)Walking at the rate of 4knph a man covers certain distance in 2hr 45 min. Running at a<br />

speed of 16.5 kmph the man will cover the same distance in.<br />

Solution::<br />

Distance=Speed* time 4*11/4=11km<br />

New speed =16.5kmph<br />

therefore Time=D/S=11/16.5 = 40min<br />

11)A train covers a distance in 50 min ,if it runs at a speed of 48kmph on an average.The<br />

speed at which the train must run to reduce the time of journey to 40min will be.<br />

Solution::<br />

Time=50/60 hr=5/6hr<br />

Speed=48mph<br />

distance=S*T=48*5/6=40km<br />

time=40/60hr=2/3hr<br />

New speed = 40* 3/2 kmph= 60kmph<br />

12)A man covers a distance on scooter .had he moved 3kmph faster he would have taken<br />

40 min less. If he had moved 2kmph slower he would have taken 40min more. the<br />

distance is.<br />

Solution::<br />

Let distance = x m<br />

Usual rate = y kmph<br />

x/y – x/y+3 = 40/60 hr<br />

2y(y+3) = 9x -------------------------------------------------1<br />

x/y-2 – x/y = 40/60 hr y(y-2) = 3x ------------------------2<br />

divide 1 & 2 equations<br />

by solving we get x = 40<br />

13)Excluding stoppages,the speed of the bus is 54kmph and including stoppages, it is<br />

45kmph.for how many min does the bus stop per hr.<br />

Solution::<br />

Due to stoppages, it covers 9km less.<br />

time taken to cover 9 km is [9/54 *60] min = 10min<br />

14)A motorist covers a distance of 39km in 45min by moving at a speed of xkmph for the<br />

first 15min.then moving at double the speed for the next 20 min and then again moving at<br />

his original speed for the rest of the journey .then x=?<br />

9


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

Solution::<br />

SITAMS<br />

Total distance = 39 km<br />

Total time = 45 min<br />

D = S*T<br />

x * 15/60 + 2x * 20/60 + x * 10/60 = 39 km<br />

x = 36 kmph<br />

15)A & B are two towns. Mr.Fara covers the distance from A to B on cycle at 17kmph<br />

and returns to A by a tonga running at a uniform speed of 8kmph.his average speed<br />

during the whole journey is.<br />

Solution::<br />

When same distance is covered with different speeds, then the average speed = 2xy / x+y<br />

=10.88kmph<br />

16)A car covers 4 successive 3km stretches at speed of 10kmph,20kmph,30kmph &<br />

60kmph resp. Its average speed is.<br />

Solution::<br />

Average speed = total distance / total time<br />

total distance = 4 * 3 = 12 km<br />

total time = 3/10 + 3/20 + 3/30 + 3/60<br />

= 36/60 hr<br />

speed =12/36 * 60 = 20 kmph<br />

17)A person walks at 5kmph for 6hr and at 4kmph for 12hr. The average speed is.<br />

Solution::<br />

avg speed = total distance/total time<br />

= 5*6 + 4*12 / 18<br />

=4 1/3 mph<br />

18)A bullock cart has to cover a distance of 80km in 10hrs. If it covers half of the journey<br />

in 3/5th time.wht should be its speed to cover the remaining distance in the time left.<br />

Solution::<br />

Time left = 10 &#8211; 3/5*10<br />

= 4 hr<br />

speed =40 km /4 hr<br />

=10 kmph<br />

19)The ratio between the speeds of the A& B is 2:3 an therefore A takes 10 min more<br />

than the time taken by B to reach the destination. If A had walked at double the speed ,he<br />

would have covered the distance in ?<br />

Solution::<br />

Ratio of speed = 2:3<br />

Ratio of time = 3:2<br />

A takes 10 min more<br />

10


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

3x-2x = 10 min<br />

A time=30 min<br />

�A covers the distance in 30 min , if its speed is x<br />

-> He will cover the same distance in 15 min, if its speed<br />

doubles (i.e 2x)<br />

20)A is twice as fast as B and B is thrice as fast as C is. The journey covered by B in?<br />

Solution::<br />

speed& ratio<br />

a : b = 2: 1<br />

b : c = 3:1<br />

Time& ratio<br />

b : c = 1:3<br />

b : c = 18:54<br />

(if c covers in 54 min i..e twice to 18 min )<br />

21)A man performed 3/5 of the total journey by ratio 17/20 by bus and the remaining<br />

65km on foot.wht is his total journey.<br />

Solution::<br />

Let total distance is x<br />

x-(3/5x + 17/20 x) =6.5<br />

x- 19x/20 = 6.5<br />

x=20 * 6.5<br />

=130 km<br />

22)A train M leaves Meerat at 5 am and reaches Delhi at 9am . Another train N leaves<br />

Delhi at 7am and reaches Meerut at 1030am At what time do the 2 trains cross one<br />

Another<br />

Solution::<br />

Let the distance between Meerut & Delhi be x<br />

they meet after y hr after 7am<br />

M covers x in 4hr<br />

N covers x in 3 ½ i.e 7/2 hr<br />

speed of M =x/4<br />

speed of N = 2x/7<br />

Distance covered by M in y+2 hr + Distance covered by N in<br />

y hr is x<br />

x/4 (y+2) +2x/7(y)=x<br />

y=14/15hr or 56 min<br />

23)A man takes 5hr 45min in walking to certain place and riding back. He would have<br />

gained 2hrs by riding both ways. The time he would take to walk both ways is?<br />

Solution::<br />

Let x be the speed of walked<br />

Let y be the speed of ride<br />

11


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

Let D be the distance<br />

Then D/x + D/y = 23/4 hr -------------------------1<br />

D/y + D/y = 23/4 – 2 hr<br />

D/y = 15/8 -------------------------------------------2<br />

substitute 2 in 1<br />

D/x + 15/8 = 23/4<br />

D/x = 23/4 -15/8 =46-15/8 =31/8<br />

Time taken for walk one way is 31/8 hr<br />

time taken to walk to and fro is 2*31/8 = 31/4 hr<br />

=7 hr 45 min<br />

24. EngineeringA train leaves a train station at 1 p.m. It travels at an average rate of 60<br />

mi/h. A high-speed train leaves the same station an hour later. It travels at an average rate<br />

of 96 mi/h. The second train follows the same route as the first train on a track parallel to<br />

the first. In how many hours will the second train catch up with the first train?<br />

Solution:<br />

25. Noya drives into the city to buy a software program at a computer store. Because of<br />

traffic conditions, she averages only 15 mi/h. On her drive home she averages 35 mi/h. If<br />

the total travel time is 2 hours, how long does it take her to drive to the computer store?<br />

12


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

26. Jane and Peter leave their home traveling in opposite directions on a straight road.<br />

Peter drives 15 mi/h faster than Jane. After 3 hours, they are 225 miles apart. Find Peter's<br />

rate and Jane's rate.<br />

27.A person crosses a 600 m long street in 5 minutes. What is his speed in km per hour?<br />

A. 3.6 B.7.2<br />

C. 8.4 D.10<br />

Answer: Option B<br />

SITAMS<br />

13


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

Explanation:<br />

Speed=(600/5 * 60) m/sec<br />

SITAMS<br />

= 2 m/sec.<br />

Converting m/sec to km/hr (see important formulas section)<br />

=(2*18/5) km/hr<br />

= 7.2 km/hr.<br />

28. An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover<br />

the same distance in 1 hours, it must travel at a speed of:<br />

A. 300 kmph B.360 kmph<br />

C. 600 kmph D.720 kmph<br />

Answer: Option D<br />

Explanation:<br />

Distance = (240 x 5) = 1200 km.<br />

Speed = Distance/Time<br />

Speed = 1200/(5/3) km/hr. [We can write 1 hours as 5/3 hours]<br />

Required speed =(1200 * 3/5) km/hr= 720 km/hr.<br />

29. If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more.<br />

The actual distance travelled by him is:<br />

A. 50 km B.56 km<br />

C. 70 km D.80 km<br />

Answer: Option A<br />

Explanation:<br />

Let the actual distance travelled be x km.<br />

Then x/10=(x+20)/14<br />

14x = 10x + 200<br />

4x = 200<br />

x = 50 km.<br />

14


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

30. A train can travel 50% faster than a car. Both start from point A at the same time and<br />

reach point B 75 kms away from A at the same time. On the way, however, the train<br />

lost about 12.5 minutes while stopping at the stations. The speed of the car is:<br />

A. 100 kmph B.110 kmph<br />

C. 120 kmph D.130 kmph<br />

SITAMS<br />

Answer: Option C<br />

Explanation:<br />

Let speed of the car be x kmph.<br />

Then, speed of the train=(150/100)*x=(3/2)*x kmph<br />

(75/x)-(75/(3/2x))=125/(10*60)<br />

(75/x)-(50/x)=5/24<br />

x = 25 x24 = 120 kmph.<br />

5<br />

31. Excluding stoppages, the speed of a bus is 54 kmph and including stoppages, it is 45<br />

kmph. For how many minutes does the bus stop per hour?<br />

A. 9 B.10<br />

C. 12 D.20<br />

Answer: Option B<br />

Explanation:<br />

Due to stoppages, it covers 9 km less.<br />

Time taken to cover 9 km = 9 x 60 min = 10 min.<br />

54<br />

32. In a flight of 600 km, an aircraft was slowed down due to bad weather. Its average<br />

speed for the trip was reduced by 200 km/hr and the time of flight increased by 30<br />

minutes. The duration of the flight is:<br />

A. 1 hour B.2 hours<br />

C. 3 hours D.4 hours<br />

Answer: Option A<br />

Explanation:<br />

Let the duration of the flight be x hours.<br />

Then, 600- 600 = 200<br />

15


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

x x + (1/2)<br />

600 - 1200 = 200<br />

x 2x + 1<br />

x(2x + 1) = 3<br />

2x 2 + x - 3 = 0<br />

(2x + 3)(x - 1) = 0<br />

x = 1 hr. [neglecting the -ve value of x]<br />

33. A man complete a journey in 10 hours. He travels first half of the journey at the rate<br />

of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km.<br />

A. 220 km B.224 km<br />

C. 230 km D.234 km<br />

Answer: Option B<br />

Explanation:<br />

(1/2)x + (1/2)x = 10<br />

21 24<br />

x + x = 20<br />

21 24<br />

15x = 168 x 20<br />

x = 168 x 20 = 224 km.<br />

15<br />

34. The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 kms in<br />

4 hours, then the speed of the first train is:<br />

A. 70 km/hr B.75 km/hr<br />

C. 84 km/hr D.87.5 km/hr<br />

Answer: Option D<br />

Explanation:<br />

Let the speed of two trains be 7x and 8x km/hr.<br />

Then, 8x = 400 = 100<br />

4<br />

x = 100 = 12.5<br />

8<br />

16


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

Speed of first train = (7 x 12.5) km/hr = 87.5 km/hr.<br />

35. A man on tour travels first 160 km at 64 km/hr and the next 160 km at 80 km/hr. The<br />

average speed for the first 320 km of the tour is:<br />

A. 35.55 km/hr B.36 km/hr<br />

C. 71.11 km/hr D.71 km/hr<br />

Answer: Option C<br />

Explanation:<br />

Total time taken = 160 + 160<br />

hrs. =9 64 80<br />

hrs.<br />

2<br />

Average speed = 320 x 2<br />

9<br />

= 71.11 km/hr.<br />

km/hr<br />

36.<br />

A car travelling with of its actual speed covers 42 km in 1 hr 40 min 48 sec. Find the<br />

actual speed of the car.<br />

A. 17 6 km/hr<br />

B.25 km/hr<br />

7<br />

C. 30 km/hr D.35 km/hr<br />

Answer: Option D<br />

Explanation:<br />

Time taken = 1 hr 40 min 48 sec = 1 hr 40 4 min = 1 51 hrs = 126 hrs.<br />

5 75 75<br />

Let the actual speed be x km/hr.<br />

Then, 5 x x 126 = 42<br />

7 75<br />

x = 42 x 7 x 75 = 35 km/hr.<br />

5 x 126<br />

37. In covering a distance of 30 km, Abhay takes 2 hours more than Sameer. If Abhay<br />

doubles his speed, then he would take 1 hour less than Sameer. Abhay's speed is:<br />

A. 5 kmph B.6 kmph<br />

C. 6.25 kmph D.7.5 kmph<br />

Answer: Option A<br />

Explanation:<br />

17


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

Let Abhay's speed be x km/hr.<br />

Then, 30 - 30 = 3<br />

x 2x<br />

6x = 30<br />

x = 5 km/hr.<br />

38. Robert is travelling on his cycle and has calculated to reach point A at 2 P.M. if he<br />

travels at 10 kmph, he will reach there at 12 noon if he travels at 15 kmph. At what<br />

speed must he travel to reach A at 1 P.M.?<br />

A. 8 kmph B.11 kmph<br />

C. 12 kmph D.14 kmph<br />

Answer: Option C<br />

Explanation:<br />

Let the distance travelled by x km.<br />

Then, x - x = 2<br />

10 15<br />

3x - 2x = 60<br />

x = 60 km.<br />

Time taken to travel 60 km at 10 km/hr = 60<br />

10<br />

= 6 hrs.<br />

hrs<br />

So, Robert started 6 hours before 2 P.M. i.e., at 8 A.M.<br />

Required speed = 60<br />

5<br />

= 12 kmph.<br />

kmph.<br />

39. It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by<br />

car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio<br />

of the speed of the train to that of the cars is:<br />

A. 2 : 3 B.3 : 2<br />

C. 3 : 4 D.4 : 3<br />

Answer: Option C<br />

Explanation:<br />

Let the speed of the train be x km/hr and that of the car be y km/hr.<br />

18


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

Then, 120 + 480 = 8 1 + 4 = 1 x y<br />

....(i)<br />

x y 15<br />

And, 200 + 400 = 25<br />

x y 3<br />

1 2 1<br />

+ = ....(ii)<br />

x y 24<br />

SITAMS<br />

Solving (i) and (ii), we get: x = 60 and y = 80.<br />

Ratio of speeds = 60 : 80 = 3 : 4.<br />

40. A farmer travelled a distance of 61 km in 9 hours. He travelled partly on foot @ 4<br />

km/hr and partly on bicycle @ 9 km/hr. The distance travelled on foot is:<br />

A. 14 km B.15 km<br />

C. 16 km D.17 km<br />

Answer: Option C<br />

Explanation:<br />

Let the distance travelled on foot be x km.<br />

Then, distance travelled on bicycle = (61 -x) km.<br />

So, x + (61 -x) = 9<br />

4 9<br />

9x + 4(61 -x) = 9 x 36<br />

5x = 80<br />

x = 16 km.<br />

41. A man covered a certain distance at some speed. Had he moved 3 kmph faster, he<br />

would have taken 40 minutes less. If he had moved 2 kmph slower, he would have<br />

taken 40 minutes more. The distance (in km) is:<br />

A. 35 B.36 2<br />

3<br />

C. 37 1<br />

D.40<br />

2<br />

Answer: Option D<br />

Explanation:<br />

Let distance = x km and usual rate = y kmph.<br />

Then, x - x = 40 2y(y + 3) = 9x ....(i)<br />

y y + 3 60<br />

And, x - x = 40 y(y - 2) = 3x ....(ii)<br />

y -2 y 60<br />

19


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

SITAMS<br />

On dividing (i) by (ii), we get: x = 40.<br />

Each of the questions given below consists of a statement and / or a question and two<br />

statements numbered I and II given below it. You have to decide whether the data<br />

provided in the statement(s) is / are sufficient to answer the given question. Read the both<br />

statements and<br />

• Give answer (A) if the data in Statement I alone are sufficient to answer the<br />

question, while the data in Statement II alone are not sufficient to answer the<br />

question.<br />

• Give answer (B) if the data in Statement II alone are sufficient to answer the<br />

question, while the data in Statement I alone are not sufficient to answer the<br />

question.<br />

• Give answer (C) if the data either in Statement I or in Statement II alone are<br />

sufficient to answer the question.<br />

• Give answer (D) if the data even in both Statements I and II together are not<br />

sufficient to answer the question.<br />

• Give answer(E) if the data in both Statements I and II together are necessary to<br />

answer the question.<br />

42. Two towns are connected by railway. Can you find the distance between them?<br />

I. The speed of the mail train is 12 km/hr more than that of an express train.<br />

II. A mail train takes 40 minutes less than an express train to cover the distance.<br />

A. I alone sufficient while II alone not sufficient to answer<br />

B. II alone sufficient while I alone not sufficient to answer<br />

C. Either I or II alone sufficient to answer<br />

D. Both I and II are not sufficient to answer<br />

E. Both I and II are necessary to answer<br />

Answer: Option D<br />

Explanation:<br />

Let the distance between the two stations be x km.<br />

I. Then, speed of the mail train = (y + 12) km/hr.<br />

II. x x 40<br />

- = .<br />

y (y + 12) 60<br />

Thus, even I and II together do not give x.<br />

Correct answer is (D).<br />

20


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

43. The towns A, B and C are on a straight line. Town C is between A and B. The<br />

distance from A to B is 100 km. How far is A from C?<br />

I. The distance from A to B is 25% more than the distance from C to B.<br />

II. The distance from A to C is of the distance C to B.<br />

A. I alone sufficient while II alone not sufficient to answer<br />

B. II alone sufficient while I alone not sufficient to answer<br />

C. Either I or II alone sufficient to answer<br />

D. Both I and II are not sufficient to answer<br />

E. Both I and II are necessary to answer<br />

SITAMS<br />

Answer: Option C<br />

Explanation:<br />

.__________.______________________________________.<br />

A x C (100 - x) B<br />

Let AC = x km. Then, CB = (100 -x) km.<br />

I. AB = 125% of CB<br />

100 = 125 x (100 - x)<br />

100<br />

100 - x = 100 x 100 = 80<br />

125<br />

x = 20 km.<br />

AC = 20 km.<br />

Thus, I alone gives the answer.<br />

II. AC = 1 CB<br />

4<br />

x = 1 (100 - x)<br />

4<br />

x = 100<br />

x = 20.<br />

AC = 20 km.<br />

Thus, II alone gives the answer.<br />

Correct answer is (C).<br />

21


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

44. Two cars pass each other in opposite direction. How long would they take to be 500<br />

km apart?<br />

I. The sum of their speeds is 135 km/hr.<br />

II. The difference of their speed is 25 km/hr.<br />

A. I alone sufficient while II alone not sufficient to answer<br />

B. II alone sufficient while I alone not sufficient to answer<br />

C. Either I or II alone sufficient to answer<br />

D. Both I and II are not sufficient to answer<br />

E. Both I and II are necessary to answer<br />

SITAMS<br />

Answer: Option A<br />

Explanation:<br />

I gives, relative speed = 135 km/hr.<br />

Time taken = 500 hrs.<br />

135<br />

II does not give the relative speed.<br />

I alone gives the answer and II is irrelevant.<br />

Correct answer is (A).<br />

45. How much time did X take to reach the destination?<br />

I. The ratio between the speed of X and Y is 3 : 4.<br />

II. Y takes 36 minutes to reach the same destination.<br />

A. I alone sufficient while II alone not sufficient to answer<br />

B. II alone sufficient while I alone not sufficient to answer<br />

C. Either I or II alone sufficient to answer<br />

D. Both I and II are not sufficient to answer<br />

E. Both I and II are necessary to answer<br />

Answer: Option E<br />

Explanation:<br />

Since ratio of speed of X : Y is 3 : 4, then ratio of time will be 4 : 3.<br />

I. If Y takes 3 min, then X takes 4 min.<br />

II. If Y takes 36 min, then X takes 4 x 36 min = 48 min.<br />

3<br />

Thus, I and II together give the answer.<br />

Correct answer is (E).<br />

22


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

F. QUESTION BANK MOCK TEST<br />

1. Express a speed of 54 km/hr in meters/second.<br />

a)15 m/sec b)20 m/sec c)25 m/sec d)30 m/sec<br />

2.A car can cover 350 km in 4 hours. If the speed is decreased by 12 1/2 kmph, how much<br />

time does the car take to cover a distance of 450 km?<br />

a)4 hrs b)5 hrs c)2 hrs d)6 hrs<br />

3.A person covers a certain distance at a certain speed. If he increases his speed by 25 %<br />

then he takes 12 minutes less to cover the same distance. Find the time taken by him<br />

initially to cover the distance at the original speed<br />

a)3 hrs b)2 hrs c)1 hr d)7 hrs<br />

4.A car covers a certain distance going at a speed of 60 kmph and returns to the starting<br />

point at a speed of 40 kmph.Find the average speed for the whole journey.<br />

a)48 kmph b)42 kmph c)34 kmph d)40 kmph<br />

5.What is the time taken by a train running at 54 km/hr to cross a man standing on a<br />

platform, the length of the train being 180 m?<br />

a)6 seconds b)12 seconds c)16 seconds d)18 seconds<br />

6.How long will a train 100 m long and travelling at a speed of 45 kmph,take to corss a<br />

platform of length 150 m?<br />

a)20 sec b)29 sec c)27 sec d)cannot be determined<br />

7.Find the length of the bridge,which a train 120 m long travelling at 54 kmph can cross<br />

in 30 seconds.<br />

a)340 m b)350 m c)330 m d)390 m<br />

SITAMS<br />

23


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

8.A worker reaches his work place 15 minutes late by walking at 4kmph from his house.<br />

The next day he increases his speed by 2kmph and reaches in time. Find the distance from<br />

his house to his work place<br />

a)2 km b)6 km c)8 km d)3 km<br />

9.A person leaves his house and travelling at 4 kmph reaches his office 10 minutes late.<br />

Had he travelled at 7kmph he would have been 20 mins early. Find the distance from the<br />

house to the office?<br />

a)14/3 b)2 c)14/9 d)14/6<br />

10.Find the time taken by a train 150 m long running at a speed of 63 kmph to cross<br />

another train of length 100 m long running at a speed of 45 kmph in the same direction<br />

a)25 seconds b)50 seconds c)75 seconds d)100 seconds<br />

11.A train crosses two persons, cycling in the same direction as the train in 12 and 18<br />

seconds respectively. If the speeds of the two cyclists are 9 and 18 kmph respectively.<br />

Find the length and speed of the train.<br />

a)80 m b89 m c)98 m d)90 m<br />

12.Two trains running at 45 and 54 kmph cross each other in 12 seconds when they run in<br />

opposite directions. When they run in the same direction, a person in the faster train<br />

observes that he crossed the other train in 32 seconds. Find the lengths of the two trains<br />

a)250 b)450 c)260 d)234<br />

13.Two trains of length 150 m and 250m run on parallel lines. When they run in the same<br />

direction it will take 20 seconds to cross each other and when they run in opposite<br />

direction it will take 5 seconds. Find the speeds of the two trains.<br />

a)180 and 108 b)272 and 211 c)123 and 828 d)none of these<br />

SITAMS<br />

24


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

14.The average speed for an entire journey is 60 kmph without considering the stoppages.<br />

When the stoppages are considered the average speed becomes 48 kmph. How many<br />

minutes per hour on an average were the stoppages?<br />

a)10 mins b)12 mins c)16 mins d)none of these<br />

15.I had to catch a bus which was 225 m ahead of me. The bus also started at the same<br />

time. If the speed of the bus was 2.5 m/sec and my speed was 36 kmph, in how much time<br />

can i catch the bus?<br />

a)20 seconds b)25 seconds c)30 seconds d)40 seconds<br />

16.The distance from my house to my friends house is 12 km. I walked at a speed of 4<br />

kmph and after every kilometre took rest for 10 mins.How much time did it take for me to<br />

reach my friends house?<br />

a)3 hrs b)4 hrs and 50 mins c)5 hrs d)none of these<br />

17.A train covered a distance of 250 km,partly at an average speed of 40 kmph and partly<br />

at 60 kmph. Find the distance covered at 40 kmph if it took 5 hrs for the train to cover the<br />

distance.<br />

a)150 km b)120 km c)100km d)cannot be determined<br />

18.A bus covered a distance of 160 km in 4 hrs covering a part of it at 30 kmph and the<br />

remaining at 70 kmph.For how much time did the us travel at 70 kmph?<br />

a)0.5 hr b)1 hr c)1 1/2 hs d)2 hrs<br />

19.A car takes 2 hours more to cover a distance of 480 km when its speed is reduced by 8<br />

kmph. Find its usual speed<br />

a)48 kmph b)55 kmph c)60 kmph d)64 kmph<br />

SITAMS<br />

25


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

20.A person covered the first 40 km of his journey at 50 kmph,the next 70 km at 35 kmph<br />

and the remaining distance in 12 mins. If the average speed of the entire journey is 52<br />

kmph. Find the distance covered in the last stench of the journey.<br />

a)22 km b)34 km c)40 km d)46 km<br />

21.A train takes 10 seconds to cross a man standing on a platform and 44 seconds to cross<br />

the platform. What is the length of the platform. What is the length of the platform if the<br />

speed of the train is 72 kmph?<br />

a)440 m b)570 m c)680 m d)none of these<br />

22.A train travelling at 36 kmph takes 48 seconds to cross a bridge. It then crosses a man<br />

cycling at the rate of 9 kmph in the same direction in 20 seconds. Find the length of the<br />

bridge<br />

a)150 m b)220 m c)280 m d)330 m<br />

23.A train crosses two bridges 370 m and 480 m long in 51 and 62 seconds respectively.<br />

Find the speed of the train.<br />

a)24 kmph b)36 kmph c)45 kmph d)64 kmph<br />

24.A man started 15 minutes late and by travelling at a speed which is 5/4rth of his usual<br />

speed reached his office 20 mins early. What is the usual time of the journey?<br />

a)85mins b)100 mins c)135 mins d)175 mins<br />

25.A parachutist,before he opens his parachute,falls for a time t1,and covers a distance of<br />

5t1^2 and after he opens his parachute he falls for a time t2 and covers a distance Vt2.V is<br />

the velocity attained just before the parachute is opened and is given by 5t1.After what<br />

time did he open the parachute,if the total distance covered by the parachutist is 1500m<br />

and the total time is 30 seconds?<br />

a)10 seconds b)20 seconds c)18 seconds d)12 seconds<br />

SITAMS<br />

26


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

26.Akash,Anurag and Rishab are running around a circular track of length 900 m with<br />

respective speeds of 15 m , 20 m and 30 m/sec.Akash and Anurag are running in the same<br />

direction while Rishab is running in the opposite direction.After how much time will all<br />

the three of them meet for the first time?<br />

a)20 seconds b)60 seconds c)120 seconds d)180 seconds<br />

27.A police patrol party travelling at 60 kmph crosses an escaping thief travelling in the<br />

opposite direction at 48 kmph.The police party has to travel for a further 5 minutes before<br />

it can find a gap in the median where it can take a U turn and start chasing the thief.After<br />

how much time after the police party crosses the thief does it catch him?<br />

a)25 mins b)50 mins c)15 mins d)32 mins<br />

28.In a 1000 m race A reaches the goal 5 seconds earlier and beats B by 50 m.What is A's<br />

speed?<br />

a)10 m/s b)10 10/19 m/s c)9 9/19 m/s d)11 9/19 m/s<br />

29.Two points A and B are diametrically opposite points on a circular road of<br />

circumference 12 km. A cyclist started from A and made three rounds.He made the first<br />

round with a speed of 12 kmph and decreased his speed by 3 kmph for every round.What<br />

is the interval between the first time he passes through B and the third time he passes<br />

through B?<br />

a)200 mins b)100 mins c)85 mins d)170 mins<br />

30.Two men left simultaneously two places A and B.One of them left A for B while the<br />

other left B for A.Both travel each at his own uniform velocity.The first person on<br />

reaching B returns to A and then again travels bach to B and so on.What will be the<br />

distance covered by the first person when they meet for the third time given the ratio of<br />

the speed of the first person to that of the second person is 3:2 the distance between A and<br />

B is 500 m?<br />

a)1000 m b)1500 m c)2500 m d)1200 m<br />

SITAMS<br />

27


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

31.A person takes 6 hours to go by car to a certain place and return by bus.He gains 2 hrs<br />

if he goes both ways by car.How long would he have taken if he had gone by bus both<br />

ways?<br />

a)4 hrs b)6 hrs c)8 hrs d)2 hrs<br />

32.car A and car B are travelling on two perpendicular roads towards city C with equal<br />

speeds. car A starts from a distance of 100 km ar 11 a.m while car B starts from a<br />

distance of 70 km at 12 noon. At 2p.m the two cars are 50 km apart. What is the speed<br />

with which they are travelling?<br />

a)25 kmph b)20 kmph c)30 kmph d)15 kmph<br />

33.Two trains of length 200 m and 100 m simultaneously wnter a tunnel of length 300m<br />

from opposite ends at the same time on parallel tracks.The respective speeds of the two<br />

trains are 36 kmph and 18 kmph.After how much time from the instant the two trains<br />

entered the tunnel will the tunnel be free of traffic again?<br />

a)40 seconds b)30 seconds c)120 seconds d)80 seconds<br />

34.Rajat had covered one third of the total distance of his trip when his scooter failed .He<br />

then parked it and covered the remaining distance on foot, spending 20 times as long<br />

walking as riding. How many times was his riding speed more than his walking speed?<br />

a)20 b)19 c)10 d)9<br />

35.Ashish and Bali run towards each other from P and Q respectively with respective<br />

speeds of 36 kmph and 45 kmph.After meeting each other if Ashish reaches Q in 5<br />

hours,in how many hours will Bali reach P?<br />

a)3 b)3 1/5 c)4 d)8<br />

SITAMS<br />

28


REASONING AND QUANTITATIVE APTITUDE Time & Distance<br />

36.A train of length 180 m travelling at 72 kmph overtook a motorcyclist travelling at 36<br />

kmph at 4 p.m. At 5 p.m it overtook another cyclist travelling in the opposite direction at<br />

a speed of 18 kmph.When will the cyclist meet the motorcyclist?<br />

a)1 hr 20 mins b)1 hr 30 min c)1 hr 45 min d)none of the above<br />

37.Two men left simultaneously two places A and B. one of them left A for B and the<br />

other B for A. Both travelled each with his own uniform velocity. Having arrived at their<br />

destination, they turned back without stopping and turned back to their starting points.<br />

First time, they met on their own journey 18 km from B; the second time on their return<br />

journey 9 km from A. Find the distance AB.<br />

a)30 km b)45 km c)60 km d)cannot be determined<br />

38.A car travels a total distance of 150 km. After travelling a part of the distance without<br />

any trouble ,the car develops an engine problem and proceeds at 2/3rd of its former speed<br />

and arrives at the destination 48 mins late. Had the problem developed 24 km further on,<br />

the car would have arrived 12 min sooner. Find the original distance it travelled without<br />

any problem and the speed over that part of the journey.<br />

a)100km,60 kmph b)48km,36kmph c)72km,50kmph d)54km,60 kmph<br />

39. Two cyclists simultaneously start from A to B and B to A respectively. They cross<br />

each other after a time t hours. The first person reaches B in another t1 hours while the<br />

second person reaches A in another t2 hours. Then<br />

a)t=t1+t2/2 b)t=2t1t2/t1+t2 c)t=sqrt(t1t2) d)t=t2-t1/2<br />

40.Ramu starts from P towards Q at a speed of 30 kmph and after every 12 min increase<br />

his speed by 5 kmph. If the distance between P and Q is 52 km, then how much time does<br />

he take to cover the distance?<br />

a)60 min b)72 min c)90 min d)120 min<br />

SITAMS<br />

29

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