Question: Not divisible by 6

Comment on Not divisible by 6

(Alternatively) In this case the number(N)is multiple of 12 plus 3. Therefore, it must be an odd number. If we subtract an even number from and odd number we get odd number. and Odd times odd number is always odd. Choice D is the only number which will not be divisible by 6 since it will be an odd number.
gmat-admin's picture

Fantastic approach!

morshadul_h's picture

Brilliant brother ..

I found the fastest approach for this question was pugging in the values. Is that fine?
gmat-admin's picture

That's definitely a valid approach. In fact, it's one of the approaches we use in the video.

In fact, if we use your strategy to analyze the answer choices from the bottom, we get the answer faster!
gmat-admin's picture

Good point!

Hi Brent,

I have a question.

Why is 3 not divisible by 6.

When 3 divide by 6, the answer is 0.5, which gives you no remainder as well.
gmat-admin's picture

Great question!
The key here is that, in order for x to be divisible by y, it must be the case that x ÷ y = some integer.

3 ÷ 6 = 0.5, and 0.5 isn't an integer.

Here's how the Official Guide puts it:
If x and y are integers and x ≠ 0, then x is a divisor (factor) of y provided that y = xn for some integer n.

For example, 3 is a divisor of 15, because we can write 15 = (3)(5), where 5 is an integer.

Does that help?

Cheers,
Brent

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