3 friends A, B, C went for week end party to McDonald's restaurant and there they measure there weights in some order In 7 rounds. A, B, C, AB, BC, AC, ABC. Final round measure is 140kg then find the average weight of all the 7 rounds?
Options:
(A) 98.5 kgs
(B) 80 kgs
(C) 76.5 kgs
(D) 67.5 kgs
(E) 58.2 kgs
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Average weight = [(a + b + c + (a+b) + (b+c) + (c+a)+(a+b+c)] / 7 = 4 (a+b+c) /7 = 4 x 140/7 = 80 kgs So the answer is: (B).
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If the ratio of boys to girls in a class is B and the ratio of girls to boys is G; then 5 (B + G) is ?
Options:
(A) Equal to 3
(B) Less than 5
(C) More than 5
(D) Less than 1/5
(E) none of these
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Let number of boys = x
Let number of girls = y
Therefore x/y = B and y/x = G
5(B + G) = 5[(x/y) + (y/x)] = 5[(x2 + y2)/xy] > 5 So the answer is: (A).
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If 10 crates have 99 apples each and how many apples more is required in order to make 100 apples in each crate?
Options:
(A) 5
(B) 10
(C) 15
(D) 20
(E) 0
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Each crate requires 1 apples and totally there are 10 crates so required apples = 10 * 1 = 10 So the answer is: (B).
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