Rationale: Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 21 = 350 m
The answer: (A)
Question: A train running at the speed of 60 km/hr crosses a pole in 21 sec. What is the length of the train?
Options:
(A) 350 m
(B) 490 m
(C) 115 m
(D) 210 m
(E) 150 m
Reasoning: Take P = 100, then N = 50, Q = 20, M = 6. So M/N = 3/25
Ans: (E)
Question: M is 30% of Q, Q is 20% of P and N is 50% of P. What is M / N
Options:
(A) 3/28
(B) 3/27
(C) 3/21
(D) 3/22
(E) 3/25
Rationale: 400*(90/100)*(95/100) = 342
The answer: (C)
Question: The sale price sarees listed for Rs.400 after successive discount is 10% and 5% is?
Options:
(A) 345
(B) 340
(C) 342
(D) 346
(E) 341
Reasoning: The square roots of all numbers from answer choices are between 9 and 10, so the product of primes of the number we are looking should be less then 9, so this number should have only 2-s, only 3-s, only 5-s, or only 2-s and 3-s as its primes. Only 96 satisfies this.
Ans: (D)
Question: A number is said to be prime saturated if the product of all the different positive prime factors of n is less than the square root of n. What is the greatest two digit prime saturated integer ?
Options:
(A) 99
(B) 98
(C) 97
(D) 96 answer
(E) 95
Rationale: P = (P*3*R)/100
R = 33 1/3%
The answer: (B)
Question: In what time a sum of money double itself at 3% per annum simple interest?
Options:
(A) 36 1/3%
(B) 33 1/3%
(C) 33 1/6%
(D) 63 1/3%
(E) 23 1/3%
Rationale: T = 50/36 * 18/5 = 5 sec
The answer: (A)
Question: In what time will a railway train 50 m long moving at the rate of 36 kmph pass a telegraph post on its way?
Options:
(A) 5 sec
(B) 4 sec
(C) 3 sec
(D) 6 sec
(E) 1 sec