Sarah's grade was 50th percentile of the 20 grades for her class. Of the 30 grades from another class, 10 were higher than Sarah's, and the rest were lower. If no other grade was the same as Sarah's grade, then Sarah's grade was what percentile of the grades of the two classes of two classes combined?
Options:
(A) 52nd
(B) 56th
(C) 60th
(D) 70th
(E) 82nd
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52nd/56th/60th/70th/82nd So the answer is: (C).
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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
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2/5 * 6/7 * 1/3 * 1/8 = 12/840 = 1/70 So the answer is: (B).
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The average of seven numbers is 26. The average of first three numbers is 14 and the average of last three numbers is 19. What is the middle number?
Options:
(A) 25
(B) 83
(C) 29
(D) 32
(E) 34
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The total of seven numbers = 7X26 = 182
The total of first 3 and last 3 numbers is = 3 X 14+3 X 19 = 99
So, the middle number is (182 - 99 ) = 83 So the answer is: (B).
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