If n is an integer, is n/15 an integer? (1) 3n/15 is an

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If n is an integer, is n/15 an integer?

(1) 3n/15 is an integer.
(2) 8n/15 is an integer




OA B

Source: Official Guide

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by SampathKp » Tue Dec 31, 2019 1:01 pm
BTGmoderatorDC wrote:If n is an integer, is n/15 an integer?

(1) 3n/15 is an integer.
(2) 8n/15 is an integer




OA B

Source: Official Guide
From (1). 3n/15 is integer when n is multiple of 5 . so n=5, 10, 15, 20...

n/15 is an integer 15, 45 or multiple of 15 only and not when is 5, 10, 20, 25 etc, So clearly the Information is not sufficient to the answer the question.

from (2) 8n/15 is an integer for all multiples of LCM of 8 and 15. i.e 8n/15 is integer for all multiples of 120. n=120, 240, 360.

As 15 is factor of 120, it will be factor of every multiple of 120. Hence n/15 will always be an integer. Hence the information is sufficient.

Answer is B

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by swerve » Tue Dec 31, 2019 1:46 pm
BTGmoderatorDC wrote:If n is an integer, is n/15 an integer?

(1) 3n/15 is an integer.
(2) 8n/15 is an integer




OA B

Source: Official Guide

Statement 1. Tells us n is divisible by 5 but is insufficient to tell us if n is divisible by 3. Insufficient \(\Large{\color{red}\chi}\)

Statement 2. This is only possible if n is multiple of 15 as 8 does not have any prime factors same as 15. Sufficient \(\Large{\color{green}\checkmark}\)

Therefore, __B__