Hi,
I think its A
Statement 1 says that (n^2 + N) = N(N+1) is not divisible by 3. However, the rule says that the product of N consecutive integers is divisble by N, or, in this case, the product of 3 consecutive integers is divisble by 3.
Since N(N+1) is not divisible by 3, N-1 must be divisble by 3.
Statement 2 says that 3n >= K + 3 or N >= K/3 + 1, or N-1>= K/3. This means that N-1 could be a multiple of 3, but it also may not.
Whats the OA?
Divisibility question
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November Rain
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raviki8208
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neoreaves wrote:Given that n is an integer, is n - 1 divisible by 3?
(1) n^2 + n is not divisible by 3
(2) 3n +5 >= k+8 , where k is a positive multiple of 3
using 1 alone, n^2 + n is not divisible
=> (n + 1) * n is not divisible
=> n and N+1 are not multiples of 3 so, n-1 is multiple.
Sufficient
using 2 alone, 3n+5 >= k+8
can not judge n so my answer is A.
what is OA?
