Chapter 9 - XYZ Custom Plus

9.1 Problem Set
521
91. Temperature and Altitude On a certain day, the temperature
on the ground is 72 degrees Fahrenheit, and the
temperature at an altitude of A feet above the ground is
A
found from the expression 72 2 } 3
}. Find the temperature
at the following altitudes.
00
a. 12,000 feet b. 15,000 feet c. 27,000 feet
92. Perimeter of a Rectangle As you know, the expression
2l 1 2w gives the perimeter of a rectangle with length l
and width w. The garden below has a width of 3} 1 2 } feet
and a length of 8 feet. What is the length of the fence
that surrounds the garden?
3.5 ft
A
72˚F
8 ft
93. Cost of Bottled Water A water bottling company charges
$7 per month for their water dispenser and $2 for each
gallon of water delivered. If you have g gallons of water
delivered in a month, then the expression 7 1 2g
gives the amount of your bill for that month. Find the
monthly bill for each of the following deliveries.
a. 10 gallons b. 20 gallons
94. Cellular Phone Rates A cellular phone company charges
$35 per month plus 25 cents for each minute, or fraction
of a minute, that you use one of their cellular
0 1 25t
phones. The expression } 350 gives the amount of
100
money, in dollars, you will pay for using one of their
phones for t minutes a month. Find the monthly bill for
using one of their phones:
a. 20 minutes in a month b. 40 minutes in a month
WBC
WATER BOTTLE CO.
MONTHLY BILL
234 5th Street
Glendora, CA 91740
Water dispenser
Gallons of water
1
8
DUE 07/23/08
$7.00
$2.00
$23.00
Cell Phone Company
Grover Beach, CA
August 2008 DUE 08/15/08
Monthly Access per Phone:
Charges:
$0.25/minute
1
50
$35.00
$12.50
$47.50
Getting Ready for the Next Section
Add.
95. 4 1 (24)
100. 23 1 12
96. 2 1 (22)
101.
97. 22 1 (24)
98. 22 1 (25) 99. 25 1 2
5
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102. } 1 } 2 103. 2 } 3 1 } 3 104. 2 } 2 1 } 2 8 4 6 3 4 4 3 3