24.
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A runs 1 times as fast as B. If A gives B a start of 80 m, how far must the winning post be so that A and B might reach it at the same time?
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A.
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200 m
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B.
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300 m
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C.
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270 m
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D.
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160 m
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Answer: Option A
Explanation:
Ratio of the speeds of A and B =
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5
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: 1 = 5 : 3.
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3
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Thus, in race of 5 m, A gains 2 m over B.
2 m are gained by A in a race of 5 m.
80 m will be gained by A in race of
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5
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x 80
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m
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= 200 m.
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2
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Winning post is 200 m away from the starting point.
