A can do a piece of work in 20 days. B in 15 days A and C in 12 days. In how many days can A finish the work if he is assisted by B on one day and C on the next, alternately?
Options:
(A) 9 days
(B) 8 days
(C) 5 days
(D) 54 days
(E) 2 days
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A + B = 1/20 + 1/15 = 7/60
A + C = 1/20 + 1/12 = 8/60
7/60 + 8/60 = 15/60 = 1/4
4 days * 2 = 8 days So the answer is: (B).
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The total number of students in Grades 1 and 2 is 30 more than the total number of students in grades 2 and 5. How much lesser is the number of students in Grade 5 as compared to Grade 1?
Options:
(A) 20
(B) 30
(C) 10
(D) 40
(E) 15
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(Grade 1 + Grade 2) - (Grade 2 + Grade 5) = 30
Grade 1 - Grade 5 = 30 So the answer is: (B).
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If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?
Options:
(A) 22 1/9 %
(B) 22 2/2 %
(C) 23 1/2 %
(D) 22 1/2 %
(E) 62 1/2 %
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9 = (1*40*R)/100
R = 22 1/2 % So the answer is: (D).
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