Problema Solution
Mario and Kenneth work in a car wash station. The time that Mario takes in washing a car alone is 20 minutes less than the time that Kenneth takes in washing the same car. If both of them work together in washing the car,it will take them 90 minutes. How long will it take each of them to wash the car?
Answer provided by our tutors
Let 'x' represent the time Kenneth needs to wash the car then 'x - 20' is the time Mario needs to wash the car.
Kenneth's rate is: 1/x cars per minutes
Marios's rate is: 1/(x - 20) cars per minute
The together rate is 1/90 cars per minute
1/x + 1/(x - 20) = 1/90
........
click here to see the equation solved for x
........
x = 190.56 min
x - 20 = 190.56 - 20 = 170.56 min
Mario needs 170.56 minutes to wash a car alone while Kenneth needs 190.56 minute to wash a car alone.