If a positive integer "n" is divisible by both 5 and 7, then "n" must also be divisible by which of the following?
I. 12
II. 35
III. 70
(A) None
(B) I only
(C) II only
(D) I and II
(E) II and III
[spoiler]OA=C[/spoiler]
Source: Official Guide
If a positive integer n is divisible by both 5 and 7
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M7MBA wrote:If a positive integer "n" is divisible by both 5 and 7, then "n" must also be divisible by which of the following?
I. 12
II. 35
III. 70
(A) None
(B) I only
(C) II only
(D) I and II
(E) II and III
[spoiler]OA=C[/spoiler]
Source: Official Guide
Since n is divisible by both 5 and 7 it MUST be divisible by the least common multiple of 5 and 7, which is 35. If we take n = 35, we see that n is not necessarily divisible neither by 12 nor by 70.
Answer: C
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