question: How many two-digit numbers satisfy this property.: The last digit (unit's digit) of the square of the two-digit number is 3 ?
Options:
(A) 4
(B) 0
(C) 3
(D) 2
(E) 1
answer: Stream of consciousness: A number ending with 3 can never be a perfect square. The answer is (B).

q: Find the smallest number which should be multiplied with 520 to make it a perfect square.
Options:
(A) 30
(B) 120
(C) 55
(D) 35
(E) None of these
a: Stream of consciousness: 520 = 26 * 20 = 2 * 13 * 22 * 5 = 23 * 13 * 5
Required smallest number = 2 * 13 * 5 = 130
130 is the smallest number which should be multiplied with 520 to make it a perfect squar The answer is (E).

question: A train 420 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 36 sec
(B) 16 sec
(C) 17 sec
(D) 88 sec
(E) 12 sec
answer: Stream of consciousness: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 420 * 2/35 = 36 sec The answer is (A).

q: Which of the following numbers is divisible by 9?
Options:
(A) 23274
(B) 25181
(C) 31001
(D) 50123
(E) 11251
a: Stream of consciousness: 23274. This is the only option with last two digits divisible by 9 The answer is (A).

question: A 160 meter long train crosses a man standing on the platform in 12 sec. What is the speed of the train?
Options:
(A) 48 kmph
(B) 54 kmph
(C) 92 kmph
(D) 86 kmph
(E) 76 kmph
answer: Stream of consciousness: S = 160/12 * 18/5 = 48 kmph The answer is (A).

question: Two persons A and B can complete a piece of work in 30 days and 45 days respectively. If they work together, what part of the work will be completed in 3 days?
Options:
(A) 1/9
(B) 1/7
(C) 1/6
(D) 1/2
(E) 1/1
answer:
Stream of consciousness: A's one day's work = 1/30
B's one day's work = 1/45
(A + B)'s one day's work = 1/30 + 1/45 = 1/18
The part of the work completed in 3 days = 3 (1/18) = 1/6. The answer is (C).