January 28
Name:
Problems 1 - 5: Choose the best answer to each of the following questions. Explain your
reasoning with one or more complete sentences.
1. (3 pts) If you multiply an area in square feet by a height in feet, the result will have
units of
c. feet3 . feet2 × feet = feet3 .
2. (3 pts) The fact that 1 liter = 1.06 quarts can be written as the conversion factor
a. 1.06 quarts / liter. The equivalent statements are 1 = 1 liter / 1.06 quarts, and,
1 = 1.06 quarts / 1 liter.
3. (3 pts) If the current exchange rate is $ 1.368 per euro, then
b. 1 euro is worth more than $1. 1 euro = $ 1.368 ¿ $ 1.
4. (3 pts) You are given two pieces of information: (1) the price of gasoline in dollars
per gallon and (2) the gas mileage of a car in miles per gallon. You are asked to find
the cost of driving this car in dollars per mile. You should
a. divide the price of gas by the car’s gas mileage.
$
miles
$
gallon
$
÷
=
×
=
gallon gallon
gallon
mile
mile
5. (3 pts) New Mexico has a population density of about 12 people per square mile and
an area of about 120,000 square miles. To find the actual population, you should
a. multiply the population density by the area.
12people
2
2 × 120, 000mile = 1, 440, 000people
1mile
6. (3 pts) Carry out the following unit conversions.
a. Convert 23 minutes to seconds. (1 minute = 60 seconds)
23minutes 60seconds
×
= 1860seconds
1
1minute
b. Convert 18 quarts to liters. (1 liter = 1.057 quarts)
18quarts
1liter
×
≈ 17.03liter
1liter
1.057quarts
c. Convert 260 square inches to square feet. (1 foot = 12 inches)
260in2
×
1
1ft
12in
2
1ft2
260in2
2
×
=
2 ≈ 1.81ft
1
144in
7. (3 pts) Which is worth more: 1 Canadian dollar or 1 euro? Convert both values to
US dollars. (1 US dollar = 1.11 Canadian dollar, 1 US dollar = 0.73 euro)
1Can. dollar
$1
×
= $0.90
1
1.11Can. dollar
1euro
$1
×
= $1.37
1
0.73euro
8. (2 pts) Convert 16 grams per centimeter to pounds per inch. (1 kilogram = 2.205
pounds, 1 kilogram = 1000 grams, 1 centimeter = 0.3937 inches)
16g
1cm
1kg
2.205lb
0.0896lb
×
×
×
≈
1cm 0.3937in 1000g
1kg
in
9. (3 pts) A 1-hour bike ride at a pace of 15 miles per hour consumes about 750 Calories. What is your average power output, in watts, during a 45-minute bike ride?
(1 Calorie = 4184 Joules, 1 watt = 1 Joule
)
sec
Total Calories used in a 45-minute ride:
750Cal
= 562.5Cal
45minutes ×
60minutes
Rate of Calories used in a 45-minute ride:
1minute
Joules
× 60seconds
× 4184Joules
≈ 871.7 second
1Cal
Then the average power output is 871.7 watts.
562.5Cal
45minutes