Question

Maria and two friends drove 87.5 miles and averaged 35 miles per gallon. They drove at an average speed of 50 miles per hour, and the gas cost $3.89per gallon. Find the quantities 10 that are expressed with each of these units.

a) Gallons
b) hours
c) dollars/passenger
d) feet/second
e) cents/mile

Answer 1

a) 2.5 gallons

b) 1.75 hours

c) $3.24/passenger

d) 73.33 feet/second

e) 11.11 cents/mile

Explanation:

a) Gallons - amount of gas used:

`A = (1\ gallon)/(35\ miles)*87.5\ miles\\ A=2.5\ gallons`

b) hours - time spent on the trip

`B = (1\ hour)/(50\ miles)*87.5\ miles\\ B=1.75\ hours`

c) dollars/passenger - amount spent per passenger on gas

`C =(\$3.89)/(gallon)*2.5\ gallon*(1)/(3\ passengers) \\ C=\$3.24\ /passenger`

d) feet/second - average speed of the trip

`D=(50\ miles)/(hour)*(hour)/(3,600\ seconds)*(5,280\ feet)/(mile)\\ D=73.33\ feet/ second`

e) cents/mile - money, in cents, spent per mile traveled

`E =(\$3.89)/(gallon)*(100\ cents)/(\$) *2.5\ gallon*(1)/(87.5\ miles) \\ E=11.11\ cents /mile`