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

Q: Problem: of the diplomats who attended a summit conference : 20 spoke japanese , 32 did not speak russian and 20 % of the diplomats spoke neither japanese nor russian . if 10 % of the diplomats spoke both japanese and russian , then how many diplomats attended the conference ?

A: 120
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Q: Problem: what is the sum of natural numbers between 30 and 100

A: 4615
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Q: Problem: village x has a population of 72000 , which is decreasing at the rate of 1200 per year . village y has a population of 42000 , which is increasing at the rate of 800 per year . in how many years will the population of the two villages be equal ?

A:
15
****