Rationale: D = 25 * 60 + 1500 = 3000 m
T = 3000/60 * 18/5 = 180 sec = 3 mins
The answer: (B)
Question: A train of 24 carriages, each of 60 meters length, when an engine also of 60 meters length is running at a speed of 60 kmph. In what time will the train cross a bridge 1.5 km long?
Options:
(A) 4
(B) 3
(C) 5
(D) 7
(E) 9
Reasoning: S = 240/6 * 18/5 = 144 kmph
Ans: (B)
Question: A 240 meter long train crosses a man standing on the platform in 6 sec. What is the speed of the train?
Options:
(A) 229
(B) 144
(C) 278
(D) 126
(E) 112
Rationale: 5 is the only prime number or odd number in the series.
The answer: (C)
Question: Find the wrong number below mentioned series
5,24,60,120,210,340
Options:
(A) 340
(B) 210
(C) 5
(D) 60
(E) none
Reasoning: Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 - 780 = 46.
Ans: (A)
Question: The average of 13 numbers is 60. Average of the first 7 of them is 57 and that of the last 7 is 61. Find the 8th number?
Options:
(A) 46
(B) 77
(C) 88
(D) 544
(E) 33
Rationale: Area of an equilateral triangle = 3/4 S2
If S = 20, Area of triangle = 3/4 * 20 * 20 = 1003 cm2;
The answer: (E)
Question: What is the are of an equilateral triangle of side 20 cm?
Options:
(A) 645
(B) 649
(C) 644
(D) 643
(E) 1003
Rationale: Population after n years = P [1 + (R/100)]2
Population after 2 years = 150000 * [1 + 6/100]2 = (150000 x 53/50 x 53/50) = 168540
The answer: (C)
Question: he population of a city is 150,000. If it increases at the rate of 6% per annum, then what will be its population 2 years hence?
Options:
(A) 1697787
(B) 1697723
(C) 168540
(D) 169728
(E) 169718