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

Ex Input:
Problem: a can do a work in 15 days and b in 20 days . if they work on it together for 7 days , then the fraction of the work that is left is

Ex Output:
11 / 6


Ex Input:
Problem: if the radius of a circle is decreased 60 % , what happens to the area ?

Ex Output:
84 % decrease


Ex Input:
Problem: it is decided to construct a 2 metre broad pathway around a rectangular plot on the inside . if the area of the plots is 96 sq . m . and the rate of construction is rs . 50 per square metre . , what will be the total cost of the construction ?

Ex Output:

insufficient data', 'd ) rs . 4400', 'e ) none of these'