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

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).

An analyst will recommend a combination of 3 industrial stocks, 2 transportation stocks, and 2 utility stocks. If the analyst can choose from 5 industrial stocks, 4 transportation stocks, and 4 utility stocks, how many different combinations of 7 stocks are possible?
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Options:
(A) 12
(B) 19
(C) 360
(D) 580
(E) 720

5C3 * 4C2 * 4C2 = 10*6*6 = 360. So the answer is: (C).

A can do a work in 9 days and B can do the same work in 18 days. If they work together, in how many days will they complete the work?
Options:
(A) 6 days
(B) 7 days
(C) 5 days
(D) 3 days
(E) 2 days

One day's work of A and B = 1/9 + 1/8 = (2+1)/18 = 1/6 So, the time taken to complete the work is 6 days. So the answer is: (A).

A corporation triples its annual bonus to 50 of its employees. What percent Q of the employees' new bonus is the increase?
Options:
(A) 50%
(B) 6623%
(C) 100%
(D) 200%
(E) 300%
Q of the employees' new bonus is the increase Hence So the answer is: (B).