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# Is n prime?

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Please note that nowhere we are given in the question that 'n' is an integer.

Statement 1. n is between 1 and 4.

Now if n is an integer, then there are only 2 possible values: 2 and 3 - both of which are prime.
But if n is not an integer, then there are infinite values possible: 2.01, 2.456, 3.97 etc- which are obviously not prime.

So Insufficient.

Statement 2. n^2 - 5n + 6 = 0

We can factorise this quadratic equation:
n^2 - 3n - 2n + 6=0
(n-3)(n-2) = 0
So either n=3 or n=2, Both of which are prime .

Sufficient - this gives YES as an answer to the question asked.

Hence B is the anwer
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Stmnt 1: 1<n<4 . Can be 1.5, 1.2,...3.9 : Not Suff

Stmnt 2: n^2 − 5n + 6 = 0 : => (n-3)(n-2)=0
So either n = 3 or n=2 , and since both 3 and 2 are prime numbers therefore B is sufficient.
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