q: The average of 13 numbers is 60. Average of the first 7 of them is 55 and that of the last 7 is 61. Find the 8th number?
Options:
(A) 32
(B) 83
(C) 45
(D) 53
(E) 64
a: Stream of consciousness: Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 55 = 385
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 385 - 780 = 32. The answer is (A).
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q: Find the largest 4 digit number which isexactly divisible by 88?
Options:
(A) 2413
(B) 4356
(C) 9944
(D) 7939
(E) 4674
a: Stream of consciousness: Largest 4 digit number is 9999
After doing 9999 88 we get remainder 55
Hence largest 4 digit number exactly divisible by 88 = 9999 - 55 = 9944 The answer is (C).
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q: In how many different ways can the letters of the word 'CASES' be arranged?
Options:
(A) 250
(B) 280
(C) 60
(D) 310
(E) 360
a:
Stream of consciousness: Number of ways = 5!/2! = 5X4X3X2X1/2X1 = 60 The answer is (C).
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