question: The average of 11 results is 55, if the average of first five results is 49 and that of the last seven is 52. Find the fifth result?
Options:
(A) 4
(B) 5
(C) 7
(D) 8
(E) 9
answer: Stream of consciousness: 1 to 11 = 11 * 55 = 605
1 to 5 = 5 * 49 = 245
5 to 11 = 7 * 52 = 364
5th = 245 + 364 – 605 = 4 The answer is (A).


q: A train running at the speed of 90 km/hr crosses a pole in 10 seconds. Find the length of the train.
Options:
(A) 150
(B) 180
(C) 250
(D) 200
(E) 225
a: Stream of consciousness: Speed = 90*(5/18) m/sec = 25 m/sec
Length of Train (Distance) = Speed * Time
25 *10 = 250 meter The answer is (C).


question: When tossed, a certain coin has equal probability of landing on either side. If the coin is tossed 3 times, what is the probability that it will land twice on heads and once on tails?
Options:
(A) 1/16
(B) 1/3
(C) 1/6
(D) 1/2
(E) 1/8
answer: Stream of consciousness: Must be once on twice and once on tails
1/2*1/2*1/2 = 1/8 The answer is (E).


q: If Rs.7500 are borrowed at C.I at the rate of 4% per annum, then after 2 years the amount to be paid is?
Options:
(A) 2287
(B) 2689
(C) 1667
(D) 8112
(E) 1691
a: Stream of consciousness: A = 7500(26/25)2 = 8112 The answer is (D).


question: In 1 kg mixture of sand and iron, 20% is iron. How much sand should be added so that the proportion of iron becomes 10%?
Options:
(A) 1 kg
(B) 200 gms
(C) 800 gms
(D) 1.8 kg
(E) None of these
answer: Stream of consciousness: In 1 kg mixture quantity of iron = 200 gm
Let x gm sand should be added, then
10% of (1000 + x) = 200
\ x = 1000 gm = 1 kg The answer is (A).


question: Which of the following numbers is divisible by each one of 3, 7, 9 and 11 ?
Options:
(A) 2079
(B) 456
(C) 974
(D) 562
(E) 300
answer:
Stream of consciousness: 639 is not divisible by 7
2079 is divisible by each of 3, 7, 9, 11. The answer is (A).