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

Answer: 2520


Question: Problem: what is 82 % of 3 / 5 ?

Answer: 0.492


Question: Problem: the dimensions of a room are 25 feet * 15 feet * 12 feet . what is the cost of white washing the four walls of the room at rs . 7 per square feet if there is one door of dimensions 6 feet * 3 feet and three windows of dimensions 4 feet * 3 feet each ?

Answer:
s . 6342