Bunuel
If x, n, and m are positive integers and x/n = m, is x divisible by 3?
(1) m is divisible by 6.
(2) n is divisible by 15.
Given: x, n, and m are positive integers and x/n = m Take: x/n = m
Multiply both sides by n to get:
x = nmTarget question: Is x divisible by 3 Statement 1: m is divisible by 6 In other words, m is a multiple of 6
So, we can write: m = 6k (for some integer k)
Since we already know that
x = nm, we can now replace m to write: x = (n)(6k)
Rewrite as: x = (n)(
3)(2)(k)
At this point we can clearly see that
x is divisible by 3Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: n is divisible by 15In other words, n is a multiple of 15
So, we can write: n = 15k (for some integer k)
Since we already know that
x = nm, we can now replace n to write: x = (15k)(m)
Rewrite as: x = (n)(
3)(5)(k)(m)
At this point we can clearly see that
x is divisible by 3Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer: D
Cheers,
Brent