question:A train running at the speed of 60 km/hr crosses a pole in 6 sec. What is the length of the train?
Options:
(A) 100 m
(B) 190 m
(C) 115 m
(D) 110 m
(E) 150 m
answer:(A)
Stream of consciousness:Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 6 = 100 m

question:The average amount with a group of seven numbers is Rs. 30. If the newly joined member has Rs. 60 with him, what was the average amount with the group before his joining the group?
Options:
(A) s. 25.6
(B) s. 25
(C) s. 16.6
(D) s. 26
(E) s. 25.6
answer:(B)
Stream of consciousness:Total members in the group = 7
Average amount = Rs. 30
Total amount with them = 7 * 30 = Rs. 210
One number has Rs. 60. So, the amount with remaining 6 people = 210 - 60 = Rs. 150
The average amount with them = 150/6 = Rs. 25

question:A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 60 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 30 minutes
(D) 27 minutes
(E) 11 minutes
answer:
(C)
Stream of consciousness:1/20 - 1/60 = 1/30
30 minutes