If P(A) = 2/15, P(B) = 4/15, and P(A B) = 6/15 Find P(B|A)
Options:
(A) 1/2
(B) 2/3
(C) 3
(D) 4/5
(E) 4/7
Answer and stream of consciousness: (C)
Stream of consciousness: P(B|A) = P(A B)/P(A)
P(B|A) = (6/15)/(2/15) = 3.

The average of 11 results is 52, 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) 34
(C) C) 66
(D) D) 76
(E) E) 74
Answer and stream of consciousness: (B)
Stream of consciousness: 1 to 11 = 11 * 52 = 572
1 to 6 = 6 * 49 = 294
6 to 11 = 6 * 52 = 312
6th = 294 + 312 572 = 34

The price of a T.V. set worth Rs. 8000 is to be paid in 20 installments of Rs. 750 each. If the rate of interest be 6% per annum, and the first installment be paid at the time of purchase, then the value of the last installment covering the interest as well will be?
Options:
(A) 7250
(B) 7200
(C) 7820
(D) 6000
(E) 2799
Answer and stream of consciousness: (A)
Stream of consciousness: Money paid in cash = Rs. 750
Balance payment = (8000- 1000) = Rs. 7250

If 1/2 of the air in a tank is removed with each stroke of a vacuum pump, what fraction of the original amount of air has been removed after 2 strokes ?
Options:
(A) 3/4
(B) 7/8
(C) 1/4
(D) 1/8
(E) 1/16
Answer and stream of consciousness:
(A)
Stream of consciousness: Left After 1st stroke = 1/2
Left After 2nd stroke = 1/2 * 1/2 = 1/4
So removed = 1- 1/4 = 3/4