Is the integer N odd?
(1) N is divisible by 3
(2)2N is divisible by twice as many positive integer as N.
Per following link:
https://www.beatthegmat.com/is-the-integ ... 81868.html
Answer is B. But I disagree. Here is why:
if you pick 9 or 18 logic adds up. but if you pick lets say 17 then 2(17) doesn't have twice as many divisors as 17 has.
am I looking at it the wrong way or is the answer really is E.
thanks
Is the integer N odd?
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Statement 1 is clearly NOT sufficient.shahab03 wrote:Is the integer N odd?
(1) N is divisible by 3
(2)2N is divisible by twice as many positive integer as N.
Per following link:
https://www.beatthegmat.com/is-the-integ ... 81868.html
Answer is B. But I disagree. Here is why:
if you pick 9 or 18 logic adds up. but if you pick lets say 17 then 2(17) doesn't have twice as many divisors as 17 has.
am I looking at it the wrong way or is the answer really is E.
thanks
Statement 2: When odd number N is doubled, 2N has twice as many factors as N.
Because odd number has only odd factors and when we multiply N by two we are left with all these odd factors as divisors and adding exactly the same number of even divisors, which are odd * 2; SUFFICIENT.
Example: No. of factors of 3 is two (1 and 3 itself) and no. of factors of 2 * 3 = 6 is four (1, 2, 3, and 6 itself), so the no. of factors of 6 = 2N is twice the no. of factors of 3 = N.
Hence, the correct answer should be B.
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