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Winner Beats Second Runner Up by...

**What was the question? **
Let** Lavesh**'s speed be **10 m/s.** Then he must have taken **10** seconds to finish the race. Since Bolt was beaten by Lavesh by **20 m** he must have run **80m** when** Lavesh** finished race in **10** seconds **(t=10).** So his speed would be** 8 m/s.**

Now** Bolt** requires** 100/0.8 = 12.5 **seconds to finish the race. When he finished, **Lewis** was **20m** behind i.e.** 80m** from starting point at** t = 12.5.** So Lewis speed is **80/12.5 = 6.4 m/s**

At **t = 10** seconds, when **Lavesh** finished his race** Lewis **must be at **6.4 x 10 = 64 m** from starting point. Hence **Lavesh** beats** Lewis **by **100 - 64 = 36 m.**

Another method.

Let** L** be the speed of** Lavesh,** **B** be the speed of** Bolt** & **W** be that of** Lewis.** Then,

**L/B = 100/80 = 5/4**

**L = (5/4) B .......(1)**

Similarly,

B/W = 100/80 = 5/4

**B = (5/4) W .......(2)**

Putting (2) into (1),

L = (5/4) x (5/4) W

L/W = 25/16

**L = (25/16) W**

For given time t, when** Lavesh** finished the race,

**Distance by L/ Distance by W = 25 / 16**

100 m/ Distance by W = 25 / 16

**Distance by W = (16 x 100) / 25 = 64.**
** **
So when Lavesh finished cross line at **100 m**, Lewis was at **64m** i.e. **36m** behind. In other words, Lavesh beats Lewis by **100 - 64 = 36 m.**

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