The task is to generate the correct answer for a given math problem.

Ex Input:
Problem: what is the sum of the multiples of 4 between 63 and 151 inclusive ?

Ex Output:
233


Ex Input:
Problem: a swimmer can swim in still water at 4 km / h . if the speed of the water current is 2 km / h , how many hours will the swimmer take to swim against the current for 5 km ?

Ex Output:
2.5


Ex Input:
Problem: two cars a and b start from boston and new york respectively simultaneously and travel towards each other at constant speeds along the same route . after meeting at a point between boston and new york the two cars a and b proceed to their respective destinations of new york and boston . car a reaches new york 80 minutes after the two cars have met and car b reaches boston 90 minutes after they have met . how long did car a take to cover the distance between boston and new york ?

Ex Output:

2 hours 20 minute