Question

In a race of one kilometer, A gives B a start of 100m and still wins by 20sec. But if A gives B a start of 25sec., B wins by 50m. The time taken by A to run one kilometer is?

Answer 1

Let the time taken by A to run 1000 meters
= x seconds
time taken by B to run 900 metres
= x+20 sec.
Speeds of A and B
=1000x,900x+20respectively
ATQ,
9501000x−1000900x+20=25
(As B is the winner now)
950x1000−1000(x+20)900=25
19x20−10x+2009=25
=171x−200x−4000
=25×20×9
29x=500
x=500/29 sec

hope it helps

Answer 2

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I hope this will help you mark me as the brainliest answer.....