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LorrieJones
May 19, 2007, 07:51 PM
Okay.. here is the question:

We have 8 pairs of white socks, 9 pairs of black socks and 11 pairs of blue socks in a box. What would be the minimum numberof schols we need to take out of the box to ensure we get a pair of the same color (you can not see what color you are picking out of box.



Answer - so far... so we have 16/46 white 18/46 black and 22/46 blue... would it be 16/46 + 15/45 for white?

That would just give me a fraction or a percentage... how would I figure the NUMBER of socks needed to pull out?

Thanks!

Lorrie

Capuchin
May 20, 2007, 01:27 AM
You need the minimum number of socks to make sure you get a pair every single time. This doesn't seem to be a probability question, as I understand it You need to work out the worst case scenario.

So the worst case is that if on the first 3 tries you pull out one of each color sock, and then on the 4th try you pull out a color that makes a pair. So my answer would be 4, because by the 4th pull you would always have a pair of socks.

If I have misunderstood the question then please can you clarify a little?

Ken 297
May 20, 2007, 04:50 AM
Not sure if I understand the question. If it is a trick question it would depend very much on the wording.
If you have 8 pairs of white socks, 9 pairs of black socks and 11 pairs of blue socks pack in a box.
Assuming they are packed in pairs. You would have to pull out one pair to ensure they match.
So the answer would be two since you asked how many socks would have to be pulled out.

If the socks are put in individually I would agree with Capuchin.

If the socks were packed individually and you had to get a match for a specific colour you would have to pull out 41 for white, 39 for black and 35 for blue.

What is a schol?