question: Find the value of y from (12)^3 x 6^4 432 = y?
Options:
(A) 2567
(B) 3589
(C) 3789
(D) 4890
(E) 5184
answer: Stream of consciousness: Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72)2 = 5184
432 12 x 62 The answer is (E).
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question: If the given two numbers are respectively 7% and 14% of a third number, then what percentage is the first of the second ?
Options:
(A) 20%
(B) 25%
(C) 18%
(D) 50%
(E) none of these
answer: Stream of consciousness: Here, l = 7 and m = 14
Therefore, first number = l/m x 100% of second number = 7/14 x 100% of second number = 50% of second number The answer is (D).
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question: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 40 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 40 minutes
(D) 27 minutes
(E) 11 minutes
answer: Stream of consciousness: 1/20 - 1/40 = 1/40
40 minutes The answer is (C).
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question: The year next to 1991 having the same calendar as that of 1990 is
Options:
(A) 1998
(B) 2001
(C) 2002
(D) 2003
(E) None of these
answer:
Stream of consciousness: We go on counting the odd days from 1991 onward still the sum is divisible by 7. The number of such days are 14 upto the year 2001. So, the calender for 1991 will be repeated in the year 2002. The answer is (C).
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