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gmatprep probability
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vaishalijain7
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ssmiles08
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probability of getting a question right is 1/2.
(1/2)^x <= 1/1000
take reciprocal, 2^x <= 1000
if you know your powers of 2, 2^10 = 1024 which is little more than 1000, so the number of questions would fall below 10.
(B)
(1/2)^x <= 1/1000
take reciprocal, 2^x <= 1000
if you know your powers of 2, 2^10 = 1024 which is little more than 1000, so the number of questions would fall below 10.
(B)
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benissleeping
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benissleeping
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ghacker
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Answer is B
We can calculate 2^10 = (32)^2
How to find 32^2
Fist unit digit is 4 (2x2)
Tens digit is ( 3*2*2) = 2 (take one to the Hundred)
Hundred digit = 3*3 +1(0verflow from tens digit) = 10
32^2 = 1024
We can calculate 2^10 = (32)^2
How to find 32^2
Fist unit digit is 4 (2x2)
Tens digit is ( 3*2*2) = 2 (take one to the Hundred)
Hundred digit = 3*3 +1(0verflow from tens digit) = 10
32^2 = 1024
