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

Example Input: Problem: ajay can ride 50 km in 1 hour . in how many hours he can ride 1000 km ?
Example Output: 20 hrs

Example Input: Problem: in a maths test , students were asked to find 5 / 16 of a certain number . one of the students by mistake found 5 / 6 th of that number and his answer was 150 more than the correct answer . find the number .
Example Output: 288

Example Input: Problem: in a group of 6 boys and 4 girls , four children are to be selected . in how many different ways can they be selected ?
Example Output:
210