question: What is the units digit of the expression 14^720^4?
Options:
(A) 8
(B) 3
(C) 4
(D) 6
(E) 0
answer: Stream of consciousness: I think answer on this one should be A too. Since we know that 14^7>20^4, as Will said one should always check if the number is positive. The answer is (A).

q: The average age of P, Q, R, S five years ago was 45 years. By including T, the present average age of all the five is 49 years. The present age of T is?
Options:
(A) 64 years
(B) 48 years
(C) 45 years
(D) 40 years
(E) None of these
a: Stream of consciousness: Present age of P, Q, R, S = 45 x 4 + 20 = 200
Present age of P, Q, R, S and T = 49 x 5 = 245
Hence, the age of T = 245 - 200 = 45 years. The answer is (C).

question: If a man can cover 16 metres in one second, how many kilometres can he cover in 3 hours 45 minutes?
Options:
(A) 118 km
(B) 162 km
(C) 216 km
(D) 1887 km
(E) 177 km
answer: Stream of consciousness: 16 m/s = 16 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 16 * 18/5 * 15/4 km = 216 km. The answer is (C).

q: At 15:00 there were 20 students in the computer lab. At 15:03 and every three minutes after that, 3 students entered the lab. If at 15:10 and every ten minutes after that 9 students left the lab, how many students were in the computer lab at 15:44 ?
Options:
(A) 7
(B) 14
(C) 25
(D) 27
(E) 30
a: Stream of consciousness: Initial no of students + 3 * (1 + No of possible 3 minute intervals between 15:03 and 15:44) -
8 *(1 + No of possible 10 minute intervals between 15:10 and 15:44)
20 + 3*14 -8 * 4 = 25 The answer is (C).

question: The average of ten numbers is 210. The average of first five numbers is 40 and the average of last four numbers is 200. What is the middle number?
Options:
(A) A) 200
(B) B) 2000
(C) C) 800
(D) D) 2100
(E) E) 1100
answer: Stream of consciousness: The total of ten numbers = 10X210 = 2100
The total of first 5 and last 4 numbers is = 5 X 40+4 X 200 = 1000
So, the middle number is (2100 - 1000 ) = 1100 The answer is (E).

question: A train 180 m long running at 70 kmph crosses a platform in 20 sec. What is the length of the platform?
Options:
(A) 208
(B) 277
(C) 350
(D) 881
(E) 271
answer:
Stream of consciousness: D = 70 * 5/18 = 20 = 388 180 = 208 The answer is (A).