question: A girl is organizing her jellybean collection in which each color has its own row. In each row, there are as many jellybeans as the number of jellybean colors. Her little brother chops each jellybean into the same number of peices as the number of jellybean colors. If the final number of jellybean pieces is m, then:
Options:
(A) m is a perfect square
(B) m is an odd number
(C) m is an even number
(D) m is a perfect cube.
(E) None
answer: Stream of consciousness: For example, if there were 4 jellybean colors, the girl would have made a 4x4 arrangement. The boy chopped up each jellybean into 4, the number of pieces would be (4*4)*4 = 64 pieces, which is a cube of 4. The answer is (D).
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question: Pipes A and B can fill a cistern in 8 and 24 minutes respectively. They are opened an alternate minutes. Find how many minutes, the cistern shall be full?
Options:
(A) 12 min
(B) 6 min
(C) 4 min
(D) 8 min
(E) 10 min
answer: Stream of consciousness: 1/8 + 1/24 = 1/6
6 * 2 = 12 The answer is (A).
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question: 60 is increased by 50%. Find the final number.
Options:
(A) 100
(B) 110
(C) 90
(D) 30
(E) 160
answer: Stream of consciousness: Final number = Initial number + 50%(original number) = 60 + 50%(60) = 60 + 30 = 90. The answer is (C).
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question: he population of a city is 150,000. If it increases at the rate of 6% per annum, then what will be its population 2 years hence?
Options:
(A) 1697787
(B) 1697723
(C) 168540
(D) 169728
(E) 169718
answer:
Stream of consciousness: Population after n years = P [1 + (R/100)]2
Population after 2 years = 150000 * [1 + 6/100]2 = (150000 x 53/50 x 53/50) = 168540 The answer is (C).
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