q: The average of 13 numbers is 60. Average of the first 7 of them is 54 and that of the last 7 is 61. Find the 8th number?
Options:
(A) 25
(B) 83
(C) 45
(D) 53
(E) 64
a: Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 54 = 378
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 378 - 780 = 25. The answer is (A).
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q: Calculate the largest 5 digit number which is exactly divisible by 77?
Options:
(A) 99111
(B) 99946
(C) 99869
(D) 99792
(E) 99654
a: Largest 4 digit number is 99999
After doing 99999 77 we get remainder 53
Hence largest 5 digit number exactly divisible by 77 = 99999 - 53 = 99946 The answer is (B).
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q: The average of first 10 odd numbers is?
Options:
(A) 11
(B) 10
(C) 19
(D) 16
(E) 13
a: Sum of 10 odd no. = 100
Average = 100/10 = 10 The answer is (B).
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q: People standing in a straight line are wearing alternating colored shirts. The pattern of shirts begins with red, followed by green, blue, and yellow. This pattern continues (red, green, blue, and yellow) until it ends with a red shirt. If there are more than 4 people in line, which of the following cannot be the number of people in the line?
Options:
(A) 17
(B) 37
(C) 49
(D) 61
(E) 72
a:
The correct answer should not take the form: 4x + 1. Hence, it is The answer is (E).
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