question: Find the average of the series : 312, 162, 132, 147 and 122?
Options:
(A) 170
(B) 175
(C) 180
(D) 185
(E) 195
answer: Stream of consciousness: Average = (312 + 162 + 132 + 147+ 122)/5 = 875/5 = 175 The answer is (B).

q: Two trains are moving at 60 kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?
Options:
(A) 6 12/13 sec
(B) 7 1/7 sec
(C) 7 2/2 sec
(D) 8 1/2 sec
(E) 7 1/9 sec
a: Stream of consciousness: 70 + 60 = 130 * 5/18 = 325/9 mps
D = 150 + 100 = 250 m
T = 250 * 9/325 = 90/13 = 6 12/13 sec The answer is (A).

question: Find the value of y from (12)^3 x 6^4 432 = y?
Options:
(A) 2354
(B) 2644
(C) 2645
(D) 4577
(E) 5184
answer: Stream of consciousness: Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72)2 = 5184
432 12 x 62 The answer is (E).

q: The floor of a rectangular room is 18 m long and 12 m wide. The room is surrounded by a veranda of width 2 m on all its sides. The area of the veranda is :
Options:
(A) 124 m2
(B) 126 m2
(C) 136 m2
(D) 158 m2
(E) None of these
a: Stream of consciousness: Area of the outer rectangle = 22 16 = 352 m2
Area of the inner rectangle = 18 12 = 216 m2
Required area = (352 216) = 136 m2 The answer is (C).

question: The average of 13 numbers is 60. Average of the first 7 of them is 57 and that of the last 7 is 61. Find the 8th number?
Options:
(A) 46
(B) 82
(C) 45
(D) 43
(E) 53
answer: Stream of consciousness: Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 - 780 = 46. The answer is (A).

question: A train is running at a speed of 40 km/hr and it crosses a post in 18 seconds. What is the length of the train?
Options:
(A) 190 metres
(B) 160 metres
(C) 180 metres
(D) 120 metres
(E) 200 metres
answer:
Stream of consciousness: Speed of the train, v = 40 km/hr = 40000/3600 m/s = 400/36 m/s
Time taken to cross, t = 18 s
Distance Covered, d = vt = (400/36) 18 = 200 m
Distance covered is equal to the length of the train = 200 m The answer is (E).