Bunuel
12 Days of Christmas 🎅 GMAT Competition with Lots of Questions & FunElvin has sent wish lists to both Santa and Mrs. Claus. What is the probability that he will receive gifts from neither of them?
(1) The probability that he will receive gifts from both Santa and Mrs. Claus is 1/4.
(2) The probability that he will receive gifts from exactly one of them is three times the probability that he will receive gifts from both.
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C
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NC
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********************************** 1
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(1) The probability that he will receive gifts from both Santa and Mrs. Claus is 1/4.
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C ******* 1/4
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NC
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********************************** 1
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The statement is not sufficient to find the other cells.
(2) The probability that he will receive gifts from both Santa and Mrs. Claus is 1/4.
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C ******** x
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NC
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********************************** 1
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x + 3x + N = 1
As we do not know the value of x, we can't find the value of N. The statement is not sufficient.
(1) + (2)
From (1) we know the value of x.
Hence, the statement combined can help us find the value of N.
Sufficient.
IMO C