question: 252 can be expressed as a product of primes as:
Options:
(A) 2 x 2 x 3 x 3 x 7
(B) 2 x 2 x 2 x 3 x 7
(C) 3 x 3 x 3 x 3 x 7
(D) 2 x 3 x 3 x 3 x 7
(E) 7 x 3 x 3 x 3 x 7
answer: Stream of consciousness: 252 = 2 x 2 x 3 x 3 x 7. The answer is (A).
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question: The no. of girls in a class are seven times the no. of boys, which value cannever be the of total students?
Options:
(A) 10
(B) 15
(C) 30
(D) 34
(E) 36
answer: Stream of consciousness: Let the boys are X, then girls are 7X, total = X+7X = 8X
So it should be multiple of 8, 30 is not a multiple of 8. The answer is (C).
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question: If a train, travelling at a speed of 90 kmph, crosses a pole in 5 sec, then the length of train is?
Options:
(A) 288
(B) 125
(C) 88
(D) 76
(E) 232
answer: Stream of consciousness: D = 90 * 5/18 * 5 = 125 m The answer is (B).
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question: During a sale, the price of a pair of shoes is marked down 10% from the regular price. After the sale ends, the price goes back to the original price. What is the percent of increase to the nearest percent from the sale price back to the regular price for the shoes?
Options:
(A) 9%
(B) 10%
(C) 11%
(D) 15%
(E) 90%
answer:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Stream of consciousness: Assume the price = 100
Price during sale = 90
Price after sale = 100
Percent increase = 10/90*100 = 11% approx. The answer is (C).
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