Retired Moderator
Joined: 07 Jun 2014
Posts: 4813
Given Kudos: 0
WE:Business Development (Energy and Utilities)
Re: If p is divisible by 7 and q is divisible by 6, pq must have
[#permalink]
15 Aug 2018, 08:18
Explanation
This problem is most easily solved with an example. If p = 7 and q = 6, then pg = 42, which has the factors 1 & 42, 2 & 21, 3 & 14, and 6 & 7. That’s 8 factors, but read carefully!
The question asks how many factors greater than 1, so the answer is 7. Note that choosing the smallest possible examples (p = 7 and q = 6) was the right move here, since the question asks “at least how many factors … ?” If testing p = 70 and q = 36, many, many more factors would have resulted.
The question asks for the minimum.