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Re: A and B ran a race of 480 m. In the first heat, A gives B a head start
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14 Nov 2022, 07:31
1. Distance of B = 432
if A takes t mins, B takes = (t + 1/10)
2. Distance of B = 336
if A takes t mins, B takes = (t - 1/30)
Therefore to run (432 - 336) = 96 m , B took time (1/30 + 1/10)
i.e 96 = (1/30 + 1/10) * Speed of B
This is the speed of B in m/min. Dividing by 60, speed of B in m/sec = 12.
Answer: A