q: The speed of a boat in upstream is 100 kmph and the speed of the boat downstream is 112 kmph. Find the speed of the boat in still water and the speed of the stream?
Options:
(A) 70, 10 kmph
(B) 106, 6 kmph
(C) 50, 60 kmph
(D) 45, 55 kmph
(E) 45, 65 kmph
a: Stream of consciousness: Speed of the boat in still water = (100+112)/2 = 106 kmph. Speed of the stream = (100-112)/2 = 6 kmph The answer is (B).


question: How much is 80% of 40 is greater than 4/5 of 25?
Options:
(A) 15
(B) 57
(C) 16
(D) 12
(E) 73
answer: Stream of consciousness: (80/100) * 40 – (4/5) * 25
32 - 20 = 12 The answer is (D).


q: A train 70 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 4 sec
(B) 16 sec
(C) 6 sec
(D) 20 sec
(E) 8 sec
a: Stream of consciousness: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 70 * 2/35 = 16 sec The answer is (A).


question: A train 140 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 15 sec
(B) 16 sec
(C) 18 sec
(D) 11 sec
(E) 8 sec
answer: Stream of consciousness: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 140 * 2/35 = 8 sec The answer is (E).


q: A class consists of 100 students, 30 of them are girls and 70 boys; 20 of them are rich and remaining poor; 40 of them are fair complexioned. The probability of selecting a fair complexioned rich girl is
Options:
(A) 3/125
(B) 1/59
(C) 1/56
(D) 1/54
(E) 1/53
a: Stream of consciousness: The probability of selecting girl is: 30/100 = 3/10
The probability of selecting rich is: 20/100 = 1/5
The probability of selecting fair complexioned is: 40/100 = 2/5
Three are independent;probability of rich and fair complexioned girl is:
(3/10) Ã—(1/5) Ã— (2/5) = 3/125 The answer is (A).


q: A train 410 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
Options:
(A) 40
(B) 87
(C) 26
(D) 21
(E) 44
a:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Stream of consciousness: Speed = 45 * 5/18 = 25/2 m/sec
Total distance covered = 410 + 140 = 550 m
Required time = 550 * 2/25 = 44 sec The answer is (E).