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) 9 sec
(B) 6 sec
(C) 8 sec
(D) 10 sec
(E) 11 sec
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T = 60/36 * 18/5 = 6 sec So the answer is: (B).
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Find the average of the first 9 natural numbers?
Options:
(A) 8
(B) 5
(C) 10
(D) 11
(E) 12
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Average of the first 'n' natural numbers = (n + 1)/2
We get (9 + 1)/2 = 5 So the answer is: (B).
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Find the average of the first 21 natural numbers?
Options:
(A) 8
(B) 9
(C) 10
(D) 11
(E) 12
--
Average of the first 'n' natural numbers = (n + 1)/2
We get (21+ 1)/2 = 11 So the answer is: (D).
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