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12.Practice.Tests.for.the.SAT_2015-2016_1128p

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12 Practice <strong>Tests</strong> <strong>for</strong> t h e <strong>SAT</strong><br />

Practice Test Four Answers and Explanations<br />

2. B<br />

Difficulty: Low<br />

Strategic Advice: Set up a proportion and do t h e arit h metic<br />

carefu ll y.<br />

Getting to <strong>the</strong> Answer:<br />

s x<br />

2 = 4.4<br />

2x = S( 4.4) = 22<br />

X = 11<br />

3. c<br />

Difficulty: Low<br />

Strategic Advice: Cross-multiply and <strong>the</strong>n simplify.<br />

Getting to <strong>the</strong> Answer:<br />

x_S<br />

-y-7<br />

7x =Sy<br />

7x _ _2f<br />

Sy - Sy<br />

7x = 1<br />

Sy<br />

4. E<br />

Difficulty: Low<br />

Strategic Advice: Look <strong>for</strong> vertical ang l es and straig h t<br />

ang l es.<br />

Getting to <strong>the</strong> Answer:<br />

Angle FA E is a vertical angle wit h angle BAC, so it is a l so 30°.<br />

T h en x = 90 + 30 = 1 20.<br />

Angle FA B <strong>for</strong>ms a straig h t ang l e wit h angle BAC,<br />

so y= 180.<br />

-<br />

-<br />

120 + 180<br />

2 2<br />

= lSO<br />

5. A<br />

Difficulty: Low<br />

Strategic Advice: Add up t h e tota l sc h oo l time and subtract<br />

from 2:30 to find t h e starting time.<br />

Getting to <strong>the</strong> Answer:<br />

Eac h class period is 1 h r and 20 minutes, or 1tor1- hours,<br />

so t h e 4 class periods are a total of 4( 1) = 6 = st<br />

h ours. T h e breaks and lunc h add up to S + S + 30 = 40<br />

minutes= cig = t of an h our. So t h e tota l sc h oo l time is<br />

st + t = 6 h ours. Six h ours be<strong>for</strong>e 2:30 is 8:30.<br />

6. c<br />

Difficulty: Medium<br />

Strategic Advice: Try using Backso l ving on t h is oneremember<br />

t h at a ll t h ree s h ou ld be integers, and x + 4 is t h e<br />

median (middl e) num ber.<br />

Getting to <strong>the</strong> Answer:<br />

(C) x= 11: 2x -8=2(1 1)-8= 14,x+4= 11 +4=1S,<br />

and 3x - 13 = 3(1 1) - 13 = 20. Our t h ree numbers, t h en,<br />

are 14, 1 S, and 20-w h ere (x + 4) is <strong>the</strong> median. C h oice (C)<br />

is correct.<br />

7. A<br />

Difficulty: Medium<br />

Strategic Advice: You want to figure out w h at b has to be in<br />

order to get $22S out of t h e net profit equation.<br />

Getting to <strong>the</strong> Answer:<br />

P(b) = 2.Sb - 100 = $22S<br />

2.Sb = $32S<br />

b= 130<br />

8. A<br />

Difficulty: Medium<br />

Strategic Advice: FOIL out (x - y)2 and t h en substitute<br />

w h at you know.<br />

Getting to <strong>the</strong> Answer:<br />

(x - y)2 = (x - y)(x - y)<br />

= x2 - xy - xy + y2<br />

=x2 _ 2xy + y2<br />

= (x2 + y2) - 2(xy)<br />

= (1 S3) - 2(36)<br />

=81<br />

9. E<br />

Difficulty: Medium<br />

Strategic Advice: Look <strong>for</strong> specia l triang l es in order to<br />

speed up your arit metic. It's rare t h at you' l l have to use<br />

t h e Pyt h agorean t h eorem more t h an once on any given<br />

question.

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