Problema Solution

craig drives 20km/hr faster than Marilyn. In the same time that Marilyn drives 225 km,Craig drives 325 km.Find the speed of each car.

Answer provided by our tutors

Let speed of Marilyn = x

=> Speed of Craig = x + 12

Time taken by Marilyn for 225 Kms = Distance / Speed

  = 225/x

Time taken by Craig to drive 325 Kms = 325 / (x+20)

 

Both times are equal

=> 225/x = 325/(x+20)

=> 325x = 225x + 225*20

=> 100x = 225*20

=> x = 225*20/100 = 45

=> Marilyn's speed = 45 kph

=> Craig's speed = 45 + 20 = 65 Kph