The average of 11 results is 53, if the average of first six results is 49 and that of the last six is 52. Find the sixth result?
Options:
(A) A) 46
(B) B) 23
(C) C) 66
(D) D) 76
(E) E) 74

1 to 11 = 11 * 53 = 583
1 to 6 = 6 * 49 = 294
6 to 11 = 6 * 52 = 312
6th = 294 + 312 583 = 23 So the answer is: (B).

252 can be expressed as a product of primes as:
Options:
(A) 2 x 2 x 3 x 3 x 7
(B) 2 x 2 x 3 x 3 x 8
(C) 2 x 2 x 3 x 3 x 6
(D) 2 x 2 x 3 x 3 x 1
(E) 2 x 2 x 3 x 3 x 2

Clearly, 252 = 2 x 2 x 3 x 3 x 7. So the answer is: (A).

Find the largest 4 digit number which isexactly divisible by 88?
Options:
(A) 5678
(B) 7654
(C) 9944
(D) 9950
(E) 10000

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 So the answer is: (C).

In what time will a railway train 52 m long moving at the rate of 24 kmph pass a telegraph post on its way?
Options:
(A) 3 sec
(B) 4 sec
(C) 8 sec
(D) 6 sec
(E) 7 sec
T = 52/24 * 18/5 = 8 se So the answer is: (C).