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

Ex Input:
Problem: 13 buckets of water fill a tank when the capacity of each bucket is 42 litres . how many buckets will be needed to fill the same tank , if the capacity of each bucket is 6 litres ?

Ex Output:
91

Ex Input:
Problem: a jeep takes 9 hours to cover a distance of 480 km . how much should the speed in kmph be maintained to cover the same direction in 3 / 2 th of the previous time ?

Ex Output:
35 kmph

Ex Input:
Problem: the average age of 50 students in a class is 14 years . if the age of teacher is also included , the average becomes 15 years , find the age of the teacher .

Ex Output:
65