Probability Question - Really easy!


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Probability Question - Really easy!

Postby Moderator_04 » Mon Dec 01, 2008 12:16 am

Q. You are given a bag full of socks of two colors black and white, all mixed up. You are blindfolded, and are asked to pick socks at random. You need to get to the office with feet dressed in socks of one color only (obviously). How many socks will you need to draw from the bag, to be sure that you'll find a pair that you can wear?


Postby Moderator_02 » Mon Dec 01, 2008 12:24 am

This is a trick question which doesn't use any probability / permutation, combination concepts at all. Solve the problem using the worst case scenario. In this case, the first two socks you draw will be of different colors. However, the third sock (no matter of what color) will always have a 'companion'. So, the answer is 3. You need to draw 3 socks from the bag, and you can always get a pair that you can wear.

There is no mention of left foot / right foot in the problem, so that complexity is not considered.

Re: Probability Question - Really easy!

Postby samuelarnold » Thu Mar 03, 2011 4:08 pm

Here there are only two colors of socks in the bag. so 3 socks want to be select to get two identical colors.

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