q: There are 3 teams each with 7 basket players. How many combinations are there if we were to pick 2 players from the 3 teams such that no team was picked twice?
Options:
(A) 50
(B) 23
(C) 147
(D) 28
(E) 45
a: There are altogether three arrangements, which are we can select two members each from team A and B, each from team A and C, and each from team B and C. For each arrangement, there are altogether 49 possibilities (7*7) since each team has 7 players. So there are a total of 147 possibilities (49*3). I hope this method is easier for you to understand. The answer is (C).
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q: The compound ratio of 2/5, 6/7, 1/3 and 1/8 is given by?
Options:
(A) 7/98
(B) 1/70
(C) 1/98
(D) 1/96
(E) 1/68
a: 2/5 * 6/7 * 1/3 * 1/8 = 12/840 = 1/70 The answer is (B).
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q: By travelling at 40 kmph, a person reaches his destination on time. He covered two-third the total distance in one-third of the total time. What speed should he maintain for the remaining distance to reach his destination on time?
Options:
(A) 20
(B) 99
(C) 77
(D) 63
(E) 61
a: Let the time taken to reach the destination be 3x hours. Total distance = 40 * 3x = 120x km
He covered 2/3 * 120x = 80x km in 1/3 * 3x = x hours So, the remaining 40x km, he has to cover in 2x hours. Required speed = 40x/2x = 20 kmph. The answer is (A).
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q: Fifteen telegenic contestants with a variety of personality disorders are to be divided into two "tribes" of four members each, tribe A and tribe B, for a competition. How many distinct groupings of two tribes are possible?
Options:
(A) 120
(B) 126
(C) 252
(D) 1200
(E) 1365
a:
My ans is 15C4 = 1365 The answer is (E).
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