q: The length of a rectangle is increased by 25% and its breadth is decreased by 20%. What is the effect on its area?
Options:
(A) 10000
(B) 18999
(C) 16990
(D) 16007
(E) 16991
a: Stream of consciousness: 100 * 100 = 10000
125 * 80 = 10000 The answer is (A).
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q: Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 6 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is?
Options:
(A) 60 gallons
(B) 100 gallons
(C) 240 gallons
(D) 180 gallons
(E) 130 gallons
a: Stream of consciousness: Work done by the waste pipe in 1 minute = 1/15 - (1/20 + 1/24) = - 1/40
Volume of 1/40 part = 6 gallons\
Volume of whole = 6 * 40 = 240 gallons. The answer is (C).
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q: A train 320 m in length crosses a telegraph post in 16 seconds. The speed of the train is?
Options:
(A) 22 kmph
(B) 77 kmph
(C) 54 kmph
(D) 72 kmph
(E) 88 kmph
a:

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: S = 320/16 * 18/5 = 72 kmph The answer is (D).
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