Saturday, May 2, 2009

Problem 8 - GMAT Number Properties


4 comments:

  1. 2^8 mod 5 = 1
    2^(8p+2) mod 5 = 4
    x = 4 + z (mod 5)

    (1) suff
    (2) Insuff

    A is the ans

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  2. This comment has been removed by the author.

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  3. I will approach this problem a little differently:
    2^8p=1(mod5)
    2^2=4(mod5)
    2^8p+2=4(mod5)
    or 2^(8p+2) + z=(4+z)(mod5)
    or x=4+z
    A is sufficient.

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  4. Please explain the answer in detail.

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