Integer N Odd?

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by kvcpk » Mon Sep 13, 2010 5:44 am
JeetGulia wrote:Is the Integer N odd?

1) N is Divisible by 3.
2) 2N is Divisible by twice as many integer as N.

OA is B.

Please help
stmt1
Let N=3,
3 is divisible by 3. 3 is ODD..YES
6 is divisible by 3. 6 is EVEN..NO
Inconsistent answers. hence INSUFF

stmt2
Let N be even. Example: N=2
2 is divisible by 1 and 2. so two divisors.
2N=4
4 is divisible by 1,2,4. So three divisors.
three is not equal to twice(two)

If N is not even, it has to be Odd.

Anyways, lets try one example.
let N=3
3 has 2 factors. 1,3
6 has 4 factors, 1,2,3,6

Point here is simple.
When N is even, the factors already include 2 factors. So even in 2N, the same 2 factors is carried.
But when N is odd, 2 factors doesnt exist in its factors. so 2N introduces the 2 factors and thus doubles the number of divisors.

pick B.
Hope this helps!!
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