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

Example Input: Problem: an aeroplane covers a certain distance of 670 kmph in 6 hours . to cover the same distance in 6 1 / 4 hours , it must travel at a speed of
Example Output: 643

Example Input: Problem: the curved surface of a sphere is 64 cm 2 . find its radius ?
Example Output: 4', 'd ) 9', 'e ) 7'

Example Input: Problem: joe needs to paint all the airplane hangars at the airport , so he buys 360 gallons of paint to do the job . during the first week , he uses 1 / 4 of all the paint . during the second week , he uses 1 / 3 of the remaining paint . how many gallons of paint has joe used ?
Example Output:
180