If 10 crates have 96 apples each and how many apples more is required in order to make 100 apples in each crate?
Options:
(A) 5
(B) 10
(C) 40
(D) 20
(E) 0
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Each crate requires 4 apples and totally there are 10 crates so required apples = 10 * 4 = 40 So the answer is: (C).
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The least number of complete years in which a sum of money put out at 20% C.I. will be more than doubled is?
Options:
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
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P(1 + 20/100)n > 2P or (6/5)n > 2
Now, (6/5 * 6/5 * 6/5 * 6/5) > 2. So, n = 4 years. So the answer is: (B).
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A can do a piece of work in 3 hours; B and C together can do it in 2 hours, which A and C together can do it in 2 hours. How long will B alone take to do it?
Options:
(A) 6hours
(B) 3hours
(C) 2hours
(D) 5hours
(E) 4hours
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A's 1 hour work = 1/3;
(B + C)'s 1 hour work = 1/2;
(A + C)'s 1 hour work = 1/2
(A + B + C)'s 1 hour work = (1/3 + 1/2) = 5/6
B's 1 hour work = (5/6 - 1/2) = 1/3
B alone will take 3 hours to do the work. So the answer is: (B).
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