a draw holds 5 navy socks, 7 white socks and 6 black socks. if two socks are selected at random without looking what is the probability that they do no match?

1 answer

1. Ways to get 2 socks out of 18
   =(18,2)=18!/(2!(18-2)!)
   =153
   Ways to get 2 navy socks
   =(5,2)
   Ways to get 2 white socks
   =(7,2)
   Ways to get 2 black socks
   =(6,2)
   So ways to get two different coloured socks
   =(153-(5,2)-(6,2)-7,2))
   out of a total possible 153 ways.
   
   Calculate the probability.
   I get less than 70%.

   Answer ID
   534718

   Created
   April 21, 2011 5:22pm UTC

   Rating
   0

   URL
   https://questions.llc/answers/534718