q: Find the average of the first 19 natural numbers?
Options:
(A) 8
(B) 9
(C) 10
(D) 11
(E) 12
a: Stream of consciousness: Average of the first 'n' natural numbers = (n + 1)/2
We get (19 + 1)/2 = 10 The answer is (C).
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q: A bullet train 140 m long is running at 60 kmph. In how much time will it pass a platform 160 m long?
Options:
(A) 34 Seconds
(B) 18 Seconds
(C) 41 Seconds
(D) 24 Seconds
(E) 29 Seconds
a: Stream of consciousness: Distance travelled = 140 + 160m = 300m
Speed = 60 * 5/8 = 50/3m
Time = 300 * 3/50 = 18 Seconds The answer is (B).
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q: The distance between West-Town to East-Town is 15 kilometers. Two birds start flying simultaneously towards one another, the first leaving from West-Town at a speed of 2 kilometers per minute and the second bird, leaving from East-Town, at a speed of 1 kilometers per minute. What will be the distance, in kilometers, between the meeting point and West-Town?
Options:
(A) 3.
(B) 7.
(C) 10.
(D) 12.
(E) 15.
a:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Stream of consciousness: Time taken by the birds to meet = 15/(2 + 1) = 5 mins
Distance traveled by the bird traveling from West-Town = 2 * 5 = 10 The answer is (C).
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