question: If 8m n = p, then which of the following represents the average (arithmetic mean) of m, n, and p, in terms of m?
Options:
(A) 2m 1
(B) 3m
(C) 6m
(D) m/5
(E) 6m/5
answer: Stream of consciousness: 8m - n = p
Add n to both sides:
8m = n + p
Add m to both sides:
9m = n + p + m
Now, divide both sides by 3
3m = (n + p + m)/3 = the average of n, p, and m The answer is (B).

q: A and B together can complete a work in 12 days. A alone can complete it in 20 days. If B does the work only for half a day daily, then in how many days A and B together will complete the work?
Options:
(A) 11 days
(B) 77 days
(C) 15 days
(D) 18 days
(E) 19 days
a: Stream of consciousness: B's 1 day work = (1/12 - 1/20) = 1/30
Now, (A + B)'s 1 day work = (1/20 + 1/60) = 1/15
So, A and B together will complete the work in 15 days. The answer is (C).

question: An archer is shooting arrows from various distances. She shoots at a target from 30 yards, 40 yards, and 50 yards. The probability that she hits within the bullseye from 30 yards is 5/6, the probability that she hits within the bullseye from 40 yards is 4/5, and the probability that she hits within the bullseye from 50 yards is 3/4. What is the probability that she hits the bullseye at least once in three shots, one from each distance listed.
Options:
(A) 104/105
(B) 119/120
(C) 139/140
(D) 9/10
(E) 14/15
answer: Stream of consciousness: The probability that she hits the bullseye at least once = 1 - (the probability that she misses the bullseye every shot)
The probability that she misses all shots = (prob that she misses from 30 yards)*(prob that she misses from 40 yards)*(prob that she misses from 50 yards)
Prob that she misses from 30 yards = 1 - 5/6 = 1/6; Prob that she misses from 40 yards = 1 - 4/5 = 1/5; Prob that she misses from 50 yards = 1 - 3/4 = 1/4
Thus the probability that she misses all shots = (1/6)*(1/5)*(1/4) = 1/120
Thus the probability that she makes at least one shot = 1 - (1/120) = 119/120 The answer is (B).

q: John makes $40 a week from his job. He earns a raise and now makes $80 a week. What is the % increase?
Options:
(A) 16%
(B) 16.66%
(C) 17.9%
(D) 18.12%
(E) 100%
a: Stream of consciousness: Increase = (40/40)*100 = (1)*100 = 100%. The answer is (E).

question: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is
Options:
(A) 1/9
(B) 1/7
(C) 1/5
(D) 1/1
(E) 1/2
answer: Stream of consciousness: 10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5 The answer is (C).

question: A box contains nine bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that atleast one bulb is good.
Options:
(A) 125/127
(B) 127/125
(C) 125/126
(D) 126/125
(E) 126/127
answer:
Stream of consciousness: Required probability = 1 - 1/126 = 125/126 The answer is (C).