Monday, June 8, 2009

Problem 33 - GMAT Number Properties


3 comments:

  1. (1) p must be a prime, sufficient
    (2) p got 1, 2, 7,14, and more Insuff

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  2. 1 and 2 Contradict:
    1: P^2 has 3 factors: Prime 1,p,p^2
    2: P is divisible by 14 means it is not a prime. Just FYI the number of factors of 14:
    14 = 2^1 x 7 ^1 = 1+1 x 1+1 = 4
    14^2 = 2^2 x 7^2 = 2+1 x 2+1 = 9

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  3. A.

    p = 2 or 3 which gives us 3 primes.

    for stmt 2: p = 28 gives more prime # than p = 42. Since we cannot come up with one particular # of primes P can give from this statement, its insufficient.

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