A train 280 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 15 sec
(B) 16 sec
(C) 18 sec
(D) 20 sec
(E) 22 sec
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Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 280 * 2/35 = 16 sec So the answer is: (B).
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There is a square with side 'a' and one octagon is inscribed in it. What will be perimeter of octagon.
Options:
(A) 8a/3
(B) 7a/3
(C) 5a/3
(D) a/3
(E) 11a/3
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Well if it's a regular octagon then it actually trisects each side of the square in which 1/3 of the lenght of the side of the square is the length of one side of the octagon. If any one has a doubt he can draw the figure and see it
Going this way lenght of a side of a octagon is a/3 and thus perimeter would be 8a/3. So the answer is: (A).
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Find the average of the first 23 natural numbers?
Options:
(A) 8
(B) 9
(C) 10
(D) 11
(E) 12
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Average of the first 'n' natural numbers = (n + 1)/2
We get (23 + 1)/2 = 12 So the answer is: (E).
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