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

Ex Input:
Problem: the sum of all the digits of the integers from 18 to 21 inclusive is 24 ( 1 + 8 + 1 + 9 + 2 + 0 + 2 + 1 = 24 ) . what is the sum t of all the digits of the integers from 0 to 99 inclusive ?

Ex Output:
900

Ex Input:
Problem: a , b and c , each working alone can complete a job in 6 , 8 and 12 days respectively . if all three of them work together to complete a job and earn $ 1170 , what will be b ' s share of the earnings ?

Ex Output:
$ 390

Ex Input:
Problem: how many multiples of 4 are less than 6540 , and also multiples of 7 ?

Ex Output:
234