question:3 friends A, B, C went for week end party to McDonald's restaurant and there they measure there weights in some order In 7 rounds. A, B, C, AB, BC, AC, ABC. Final round measure is 140kg then find the average weight of all the 7 rounds?
Options:
(A) 98.5 kgs
(B) 80 kgs
(C) 76.5 kgs
(D) 67.5 kgs
(E) 58.2 kgs
answer:(B)
Stream of consciousness:Average weight = [(a + b + c + (a+b) + (b+c) + (c+a)+(a+b+c)] / 7 = 4 (a+b+c) /7 = 4 x 140/7 = 80 kgs

question:Two trains are traveling on parallel tracks in the same direction. The faster train travels at 130 miles per hour, while the slower train travels at 100 miles per hour. At 2 o'clock the faster train is 5 miles behind the slower one. How far apart are the two trains at 5 o'clock?
Options:
(A) 60 miles
(B) 80 miles
(C) 90 miles
(D) 120 miles
(E) 85 miles
answer:(E)
Stream of consciousness:Answer = E. 85 miles
Relational speed = 130 - 100 = 30 miles per hour
In 3 hours, difference = 30 * 3 = 90 miles
Fast train trailing 5 miles, so effective difference = 90 - 5 = 85 miles

question:If a train, travelling at a speed of 90 kmph, crosses a pole in 5 sec, then the length of train is?
Options:
(A) 288
(B) 125
(C) 88
(D) 76
(E) 232
answer:
(B)
Stream of consciousness:D = 90 * 5/18 * 5 = 125 m