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

Ex Input:
Problem: a train covers a distance of 12 km in 10 minutes . if it takes 8 seconds to pass a telegraph post , then the length of the train is

Ex Output:
160 m


Ex Input:
Problem: two cubes have their volumes are in the ratio 1 : 27 . find the ratio of their surface area ?

Ex Output:
1 : 9', 'd ) 2 : 7', 'e ) 3 : 11'


Ex Input:
Problem: if x < y < z and y - x > 5 , where x is an even integer and y and z are odd integers , what is the least possible value a of z - x ?

Ex Output:

9