Question

Before the start of the car race, Tony Stewart and Jamie Mcmurray have the same amount of fuel in the car. With this fuel Tony Stewart can drive for 4 hours while Jamie can drive five hours.
After a time they realize that amount of fuel left in Tony car is 1/4th of the fuel in Jamie car.

For how long they are racing ?

Answer 1

Looks 3 hour 45 minutes. The amount of starting fuel is immaterial because absolute consumption is not the deciding variable but the draining rate per capacity. Tank capacity will only scale the problem. Let us assume the capacity to be 100 liters. After a time t Tony will have consumed @ 25 miles an hour an amount of 25*t and left with 100-25*t. Similarly Mcmurray will be left with 100-20*t. Since 100-25t=0.25*(100-20*t) the solution gives t =30/8 hours means 3 hours 45 minutes. The answer is same if you start with fuel of 50 liters.

Comments

thank you sandeep