car problem

[alison6399]

A car has travelled 40 miles at a speed of 60mph. It started its journey with 10 gallons of fuel but the tank gas been leaking throughout its journey and is now dry. The car completes 24 miles per gallon.

How much fuel does it leak per hour?

Pse show all workings. Thanx

[Physicsgirl]

the car has travelled 40 miles so the number of gallons used to do this is 40/24. This, plus the leakage =10 gallons. call x the rate of leakage per hour and you have

10 = (40/24) + (2/3)*x

so (10-(40/24))/(2/3) =x

I make the answer to be 12.5 gallons per hour.

[grasscarp]

40miles at 60mph, so 40 miles takes 40 minutes.
1 mile uses 1/24 gallon. 40 miles uses 1/24 x40 = 5/3 or 1 2/3 galls.
leak accounts for 10-1 2/3 galls or 8 1/3 gallons over a period of 40 minutes.
25/3 divided by 2 (for 20 minutes)
x 3 for 60 minutes = 12.5 gallons per hour.