The H.C.F. of two numbers is 12 and their L.C.M. is 600. If one of the numbers is 720, then the other is:
Options:
(A) 8
(B) 10
(C) 12
(D) 4
(E) 6
Answer and stream of consciousness: (C)
Stream of consciousness: Other number = (12 x 600)/720 = 10.

A fair coin is tossed repeatedly. If head appears on the first four tosses, then the probability of appearance of tail on the fifth toss is.
Options:
(A) 1/7
(B) 1/2
(C) 3/7
(D) 2/3
(E) 1/3
Answer and stream of consciousness: (B)
Stream of consciousness: Since the coin is a fair coin, every toss is independent of any other toss. Hence, the probability of appearance of tail on the fifth toss is = 1/2

Twenty percent of Country Y's yearly exports come from fruit exports. One-fourth of all fruit exports from Country Y are orange exports. If country Y generates $40 million from its orange exports, how much money does it generate from its yearly total of exports?
Options:
(A) $21.25m
(B) $800m
(C) $106.25m
(D) $127.5m
(E) $153m
Answer and stream of consciousness: (B)
Stream of consciousness: 20/100*1/4*(total) = 40
1/20*(total) = 40
(total) = 40*20 = 800

The inverse ratio of 4: 2: 1 is?
Options:
(A) 2:4:8
(B) 2:3:9
(C) 2:3:2
(D) 2:3:6
(E) 2:3:1
Answer and stream of consciousness:
(A)
Stream of consciousness: 1/4: 1/2: 1/1 = 2:4:8