Question

Trans truck get very poor gas mileage. if Tran pays $84 to fill his truck with gas and is able to drive m miles on a full tank, what expression shows his gas cost per mile? What operation does "per" indicate? Check your expression by substituting 200 miles for m. Does your answer make sense?

Answer 1

Money paid by Trans to completely fill his truck's gas tank = $84

Miles traveled by Trans' truck on full tank = m miles

Part A (Expression to show gas cost per mile)

Total Cost = (Gas Cost per Mile) × (Number of Miles)

⇒ 84 = (Gas Cost per Mile) × m

⇒ Gas Cost per Mile = 84 / m

Part B (Meaning of per)

In Gas Cost per Mile, the word 'per' indicates the division (÷) operation.

Part C (Substitute 200 miles for m)

Substituting 200 for m in the expression, we get:

Gas Cost per Mile = 84 ÷ 200

⇒ Gas Cost per Mile = $ 0.42

This indicates that to travel 1 mile, Trans needs to spend $0.42