Really stupid maths question lol.. (1 Viewer)

[Traveller0901]

Here's the question: X is a good runner and can beat Y by 10metres over a 100metre race. Y demands a 10 metre head start. So X lines up 10metres behind the starting line of the 100metre track and Y is on the normal starting line. Will it be a draw or who will win and by how much?

Answer: X wins by 1metre.


Okay, so i thought the answer was a draw and I cannot understand why X has won by 1metre.


Can someone please explain this??



Much appreciated

 

[RealiseNothing]

X runs 100m when Y has run 90m.

So both will be at the 90m mark as X passes Y.

In 100m X wins by 10m, so in 10m X wins by 1m.

So in the last 10m X will win by 1m.

 

[iStudent]

It's not a 100 Metre race anymore

 

[D94]

Y is running at a rate of 0.9X. So when X is at 100 metres, Y is at 90 metres (as described). So, when X runs 110 metres, Y will have ran 0.9*110 = 99 metres. So when X is at the finish line, Y is only 99 metres down the track of the 100 metres they need to run, hence X wins by 1 metre. X does not win by 11 metres because X has to start -10 metres from the start line.

 

[Squar3root]

wut

 

[Squar3root]

 

[Traveller0901]

Y is running at a rate of 0.9X. So when X is at 100 metres, Y is at 90 metres (as described). So, when X runs 110 metres, Y will have ran 0.9*110 = 99 metres. So when X is at the finish line, Y is only 99 metres down the track of the 100 metres they need to run, hence X wins by 1 metre. X does not win by 11 metres because X has to start -10 metres from the start line.

Cheers guys!!