Probability - drawer with socks
1) A drawer contains n=5 different and distinguishable pairs of socks (a total of 10 socks). If a person randomly selects 4 socks, what is
the probability that there is no matching pair in the sample?
2) A drawer contains n different and distinguishable pairs of socks (a total of 2n socks). A person randomly selects 2r of the socks, where
2r > n. In terms of n and r, what is the probability that there is no matching pair in the sample?