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

Ex Input:
Problem: in an election between two candidates , one got 60 % of the total valid votes , 30 % of the votes were invalid . if the total number of votes was 9000 , the number of valid votes that the other candidate got , was :

Ex Output:
2520


Ex Input:
Problem: two cycles are standing side - by - side . one cycle , which is 2.5 feets tall , casts a shadow that is 5 feets long . the other cycle is 2 feets tall . compute , in feets , the length of the shadow that the shorter cycle casts .

Ex Output:
4


Ex Input:
Problem: a shopkeeper has 280 kg of apples . he sells 30 % of these at 20 % profit and remaining 60 % at 30 % profit . find his % profit on total .

Ex Output:

24 %