Reasoning: D = 110 + 170 = 280 m
S = 36 * 5/18 = 10
T = 280 * 1/10 = 28 sec
Ans: (A)
Question: How long does a train 110 m long traveling at 36 kmph takes to cross a bridge of 170 m in length?
Options:
(A) 28
(B) 16.0
(C) 16.4
(D) 16.8
(E) 16.1
Rationale: Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 3 = 50 m
The answer: (E)
Question: A train running at the speed of 60 km/hr crosses a pole in 3 sec. What is the length of the train?
Options:
(A) 56
(B) 78
(C) 27
(D) 79
(E) 50
Reasoning: There are 39 students and every one has equal chance of being selected as a leader. Hence, the leader can be appointed in 39 ways. When one person is appointed as leader, we are left with 35 students. Out of these 38 teachers, we can select one class representative. So, a class representative can be selected in 38 ways. Hence, the number of ways in which a leader and class representative can be selected = 39 x 38 = 1482
Ans: (D)
Question: From among the 39 students in a class, one leader and one class representative are to be appointed. In how many ways can this be done?
Options:
(A) 1360
(B) 1260
(C) 1060
(D) 1482
(E) 1460
Rationale: The number of eggs must be one more than a number that is divisible by 2, 3, 4, 5, and 6 since each of these numbers leave a remainder of 1. For this to be true one less than the number must be divisible by 5, 4, and 3 (6 is 2*3 and 2 is a factor of 4 so they will automatically be a factor). 5 * 4 * 3 = 60. Then you just must find a multiple of 60 such that 60 * n + 1 is divisible by 7. 61 / 7, 121 / 7, 181 / 7, 241 / 7 all leave remainders but 301 / 7 doesn't.
The answer: (B)
Question: John has some chickens that have been laying him plenty of eggs. He wants to give away his eggs to several of his friends, but he wants to give them all the same number of eggs. He figures out that he needs to give 7 of his friends eggs for them to get the same amount, otherwise there is 1 extra egg left.
What is the least number of eggs he needs for this to be true?
Options:
(A) 201
(B) 301
(C) 401
(D) 101
(E) 501
Reasoning: (30*30)/100 = 9%loss
Ans: (A)
Question: A man sells two articles for Rs.3600 each and he gains 30% on the first and loses 30% on the next. Find his total gain or loss?
Options:
(A) 9 % loss
(B) 10% gain
(C) 450
(D) 12% loss
(E) 12% gain
Reasoning: Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 3 = 50 m
Ans: (E)
Question: A train running at the speed of 60 km/hr crosses a pole in 3 sec. What is the length of the train?
Options:
(A) 56
(B) 78
(C) 27
(D) 79
(E) 50