Have you learned binomial distribution?
There are C(25, 2) ways to choose two people out of 25. (This is the same as , just different notation, easier to type in.) For each of these, the probability is .
Have you learned binomial distribution?
There are C(25, 2) ways to choose two people out of 25. (This is the same as , just different notation, easier to type in.) For each of these, the probability is .