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Praetorian
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MartinMag
I like to use prob to solve these problems, but using counting methods as you did the answer would be:


Total number of pairs possible: C(10,2)=45

Of all those pairs, how many have the same color? : just 5, since from the hole lot there are not more than 2 shoes of equal color.

So 5/45=1/9


I have a long way to go!
I do see how you get that...

I think I was wrong when i tried picking one by one.

Thanks
Praetorian
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MartinMag, can you explain it using probability, please? thanks!
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MartinMag, can you explain it using probability, please? thanks!


Sure...

Suppose we have colors: A,B,C,D and E

Prob of getting 1 shoe of color A=2/10=1/5

After we got the A shoe we have 9 shoes left, then the prob of getting the other A shoe is 1/9

So, probability of getting 2 shoes of color A is 1/5*1/9

Since we have 5 pairs of different colors, the answer is 1/5*1/9*5


Hope it helps!

Martin
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thank you very much, it makes perfect sense!
i appreciate it.
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MartinMag
toujours28
MartinMag, can you explain it using probability, please? thanks!

Sure...

Suppose we have colors: A,B,C,D and E

Prob of getting 1 shoe of color A=2/10=1/5

After we got the A shoe we have 9 shoes left, then the prob of getting the other A shoe is 1/9

So, probability of getting 2 shoes of color A is 1/5*1/9

Since we have 5 pairs of different colors, the answer is 1/5*1/9*5


Hope it helps!

Martin


Here is another way of thinking about this probabilisticly.

Whatever color you pick for the first shoe, there is only one shoe out of the remaining 9 that match it, hence, the probability is 1/9.



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