how many integers less than 20 - brute force?

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How many positive integers less than 20 are either a multiple of 2, an odd multiple of 9, or the sum of a positive multiple of 2 and a positive multiple of 9?

A) 19
B) 18
C) 17
D) 16
E) 15

Is brute force the best way to solve?

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by Patrick_GMATFix » Fri Dec 20, 2013 6:46 pm
I'd use brute force since the number set is so small that it should take under a minute. The solution below is taken from the GMATFix App. My signature below has more info.

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