In how many ways can a group of 5 men and 2 women be made out of a total of 7 men and 3 women?
Options:
(A) 63
(B) 25
(C) 40
(D) 65
(E) 98
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Required number of ways = (7C5 x 3C2) = (7C2 x 3C1) = = 63. So the answer is: (A).
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A motorcyclist goes from Bombay to Pune, a distance of 160 kms at an average of 32 kmph speed. Another man starts from Bombay by car 2 ½ hours after the first, and reaches Pune ½ hour earlier. What is the ratio of the speed of the motorcycle and the car?
Options:
(A) 1:2
(B) 2:5
(C) 1:4
(D) 1:1
(E) 1:6
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T = 160/32 = 5 h
T = 5 - 3 = 2
Time Ratio = 5:2 = 5:2
Speed Ratio = 2:5 So the answer is: (B).
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In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:
Options:
(A) 3
(B) 4
(C) 5
(D) 8
(E) 9
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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
Speed in still water = (11 + 5)/2 kmph = 8 kmph. So the answer is: (D).
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