What is theleast number should be added to 1056, so the sum of the number is completely divisible by 23?
Options:
(A) 1
(B) 2
(C) 3
(D) 5
(E) 6
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(1056 / 23) gives remainder 21
21 + 2 = 23, So we need to add 2 So the answer is: (B).
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One fourth of one third of two fifth of a number is 15. What will be the 40% of that number is?
Options:
(A) 120
(B) 130
(C) 150
(D) 180
(E) 250
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(1/4) * (1/3) * (2/5) * x = 15 then x = 15 * 30 = 450
40% of 450 = 180 So the answer is: (D).
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If f(x) = x^2/(x^5 - 1), what is f(1/x) in terms of f(x)?
Options:
(A) 1/f(x)
(B) -f(x)
(C) 2/f(x)
(D) f(x)
(E) 3*f(x)
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If x = 2 then f(x) = 4/31 and f(1/x) = -4/31 which is equal to -f(x) So the answer is: (B).
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