Sagot :
Answer:
3 3/4 hours
Explanation:
Suppose that the amount of petrol in each of the cars, in the beginning, was M.
Now, suppose that they drove for X hours.
In that case, the amount of petrol used by one car in X hours will be = M*X /4
The amount of petrol used by the other car will be = M*X/5
Therefore, the petrol left in one car = M - M*X / 4
Petrol left in the other car = M - M*X / 5
Now, according to the question,
M - M*X / 5 = 4 (M - M*X / 4)
=> X = 15 / 4 = 3 3/4 hours.
Therefore Murphy and Cooper drove for 3 3/4 hours.
Step-by-step explanation: