question: An archer is shooting arrows from various distances. She shoots at a target from 50 yards, 60 yards, and 70 yards. The probability that she hits within the bullseye from 50 yards is 3/4, the probability that she hits within the bullseye from 60 yards is 2/3, and the probability that she hits within the bullseye from 70 yards is 3/5. What is the probability that she hits the bullseye at least once in three shots, one from each distance listed.
Options:
(A) 9/10
(B) 14/15
(C) 19/20
(D) 29/30
(E) 39/40
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 every shot = (prob that she misses from 50 yards)*(prob that she misses from 60 yards)*(prob that she misses from 70 yards)
Prob that she misses from 50 yards = 1 - 3/4 = 1/4; Prob that she misses from 60 yards = 1 - 2/3 = 1/3; Prob that she misses from 70 yards = 1 - 3/5 = 2/5
Thus the probability that she misses all shots = (1/4)*(1/3)*(2/5) = 1/30
Thus the probability that she makes at least one shot = 1 - (1/30) = 29/30 The answer is (D).

q: What is the probability that Company G's advertisement will be one of the first two be shown during the first commercial break?
Options:
(A) 1/ 225
(B) 1 / 30
(C) 1 /15
(D) 2 / 15
(E) 4 /15
a: Stream of consciousness: G 1/15 + (14/15) * 1/14 = 2/15 The answer is (D).

question: If P(A) = 2/15, P(B) = 7/15, and P(A B) = 16/15 Find P(A|B)
Options:
(A) 1/2
(B) 16/7
(C) 3/2
(D) 4/5
(E) 4/7
answer: Stream of consciousness: P(A|B) = P(A B)/P(B)
P(A|B) = (16/15)/(7/15) = 16/7. The answer is (B).

q: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is
Options:
(A) 1/10
(B) 9/10
(C) 1/5
(D) 3/10
(E) 1/2
a: 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 person spends 40% of his salary on food, 25% on house rent, 15% on entertainment and 10% on conveyance. If his savings at the end of the month is Rs. 1200, then his salary per month in rupees is:
Options:
(A) 12000
(B) 6000
(C) 8000
(D) 10000
(E) None of these
answer: Stream of consciousness: Total expenditure = 40 + 25 + 15 + 10 = 90%
Saving = (100 - 90) = 10%
10/100 Salary = 1200, Salary = 12000 Rs. The answer is (A).

question: If a man can cover 32 metres in one second, how many kilometres can he cover in 3 hours 45 minutes?
Options:
(A) 118 km
(B) 162 km
(C) 1767 km
(D) 432 km
(E) 177 km
answer:
Stream of consciousness: 32 m/s = 32 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 32 * 18/5 * 15/4 km = 432 km. The answer is (D).