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

Ex Input:
Problem: two trains of equal length , running with the speeds of 60 and 90 kmph , take 50 seconds to cross each other while they are running in the same direction . what time will they take to cross each other if they are running in opposite directions ?

Ex Output:
6.6


Ex Input:
Problem: a certain rectangular crate measures 8 feet by 14 feet by 16 feet . a cylindrical gas tank is to be made for shipment in the crate and will stand upright when the crate is placed on one of its six faces . what should the radius of the tank be if it is to be of the largest possible volume ?

Ex Output:
6


Ex Input:
Problem: the dimensions of a rectangular solid are 4 inches , 5 inches , and 12 inches . if a cube , a side of which is equal to one of the dimensions of the rectangular solid , is placed entirely within thespherejust large enough to hold the cube , what the ratio of the volume of the cube to the volume within thespherethat is not occupied by the cube ?

Ex Output:

10 : 2