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

Problem: find the cost of fencing around a circular field of diameter 16 m at the rate of rs . 3 a meter ?
150.84

Problem: 90 % of the population of a village is 36000 . the total population of the village is ?
4000

Problem: a multiple choice test consists of 4 questions , and each question has 5 answer choices . in how many ways can the test be completed if every question is unanswered ?

625