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

Q: Problem: the curved surface of a sphere is 64 π cm 2 . find its radius ?

A: 4', 'd ) 9', 'e ) 7'
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Q: Problem: how many positive integers less than 20 can be expressed as the sum of a positive multiple of 2 and a positive multiple of 3 ?

A: 14
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Q: Problem: a bag contains 3 red , 5 yellow and 4 green balls . 3 balls are drawn randomly . what is the probability that the balls drawn contain balls of different colours ?

A:
3 / 11
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