Reasoning: Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 18 = 300 m
Ans: (C)
Question: A train running at the speed of 60 km/hr crosses a pole in 18 sec. What is the length of the train?
Options:
(A) 356
(B) 278
(C) 300
(D) 279
(E) 150
Rationale: T = 60/36 * 18/5 = 6 sec
The answer: (D)
Question: In what time will a railway train 60 m long moving at the rate of 36 kmph pass a telegraph post on its way?
Options:
(A) 3
(B) 4
(C) 5
(D) 6
(E) 7
Reasoning: We need a number that is a multiple of 7 that will give a remainder of 1 when divided by 2, 3, 4, 5, and 6. The least common multiple of these numbers is 60. So, we need a multiple of 7 that is 1 greater than a multiple of 60.
Ans: (B)
Question: There are seven thieves. They stole diamonds from a diamond merchant and ran away. While running, night sets in and they decide to rest in the jungle.
When everybody was sleeping, two of them woke up and decided to divide the diamonds equally among themselves. But when they divided the diamonds equally, one diamond is left.
So they woke up the 3rd thief and tried to divide the diamonds equally again but still one diamond was left. Then they woke up the 4th thief to divide the diamonds equally again, and again one diamond was left. This happened with the 5th and 6th thief one diamond was still left.
Finally, they woke up the 7th thief and this time the diamonds were divided equally.
How many diamonds did they steal in total?
Options:
(A) 2397
(B) 2401
(C) 2411
(D) 2423
(E) None of the above
Rationale: The correct answer should not take the form: 5x + 2. Hence, it is
The answer: (E)
Question: People standing in a straight line are wearing alternating colored shirts. The pattern of shirts begins with red, followed by green, blue, white and yellow. This pattern continues (red, green, blue, white and yellow) until it ends with a green shirt. If there are more than 5 people in line, which of the following cannot be the number of people in the line?
Options:
(A) 22
(B) 42
(C) 52
(D) 62
(E) 71
Reasoning: Average of the first 'n' natural numbers = (n + 1)/2
We get (25 + 1)/2 = 13
Ans: (C)
Question: Find the average of the first 25 natural numbers?
Options:
(A) 8
(B) 9
(C) 13
(D) 11
(E) 12
Reasoning: Let the length W of the rectangle be 100x, and width be 100y. Area = 100x * 100y = 10000xy
Now after the change Length = 85x, and width = 140 y. Area = 11900xy
% Change = (11900xy - 10000xy)/(10000xy) = 19 % Increase. Hence
Ans: (D)
Question: The length W of a rectangle is decreased by 15% and its width is increased by 40%. Does the area of the rectangle decrease or increase and by what percent?
Options:
(A) Decreases by 19%
(B) Decreases by 25%
(C) Increases by 6%
(D) Increases by 19%
(E) Increases by 25%