Let n be a perfect square. Is n divisible by 3?

Question

(1) The square root of n is divisible by 3.
(2) n – 1 is even.

nayakr1127 · Answer

A is sufficient.
If sq root divisible by 3, then of course the square would be

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Vinayak Shenoy · Answer

IMO A
n is a perfect square

from statement 1
sqrt of n is divisible by 3
Therefore n must also be divisible by 3

from statement 2
n-1= even tells us that n is odd. n can be 9, 25, 49
insufficient

manhasnoname · Answer

If a number is divisible by n, then the square of that number is also divisible by n.

Therefore, A.

alphastallion · Answer

stmt 1: Square root of n is divisible by 3,hence the number must be multiple of 3,hence the answer will also be divisible by 3,hence A is sufficient

stmt 2: n-1 is even ,hence 3-1 is also even ,7-1 is also even ,9-1 is also even,

mutliple answer choice first two will not divided by 3,while 9 is divisible by3.hence insufficient

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