10 books are placed at random in a shelf. The probability that a pair of books will always be together is?
Options:
(A) 1/0
(B) 1/3
(C) 1/5
(D) 1/2
(E) 1/1
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10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5 So the answer is: (C).
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Find the least number must be subtracted from 427398 so that remaining no.is divisible by 15?
Options:
(A) 3
(B) 5
(C) 7
(D) 8
(E) 9
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On dividing 427398 by 15 we get the remainder 3, so 3 should be subtracted So the answer is: (A).
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A frame 2 inches wide is placed around a rectangular picture with dimensions 8 inches by 12 inches. What is the area of the frame, in square inches?
Options:
(A) 44
(B) 96
(C) 128
(D) 144
(E) 168
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A frame 2 inches wide is placed around a rectangular picture with dimensions 8 inches by 12 inches. What is the area of the frame, in square inches?
(12*16)-(8*12) = 96 So the answer is: (B).
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