Tough Puzzles & Brain Teasers
Puzzles on logic and mathematics that will make you scratch your head.
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Ankita Katdare
Computer Science
05 Jan 2019

# 10 black socks and 10 white socks puzzle - What is the correct solution?

There are 10 black socks and 10 white socks in a drawer.
Now you have to go out wearing your shoes.
So how many maximum number of times you need to remove the sock from drawer so that you can go out?
You can remove only 1 sock at a time.
Obviously, you can’t go outside wearing different socks!

Mohit Patil
Computer Science
3mos ago

I think this one is quite simple. The answer is 3.

You need maximum 3 moves.

1st sock or 2nd sock will be either black or white; if both are black or white, we are done otherwise: 3rd sock will complete the pair

2mos ago

Probability of taking 2 socks is 20C2

Probability of 2 black socks is 10C2/20C2 = 2/38

Probability of 2 white socks is 10C2/20C2 =2/38

probability of picking 2 socks of any color = 2/38+ 2/38 =4/28=2/19