Question

In a psychology class there are 13 men and 12 women. 2 students are randomly selected to present a topic. What is the probability that at least 1 of the 2 students selected is male? Express your answer as a fraction or a decimal number rounded to four decimal places.

Answer 1

Answer

total number of students = 12+13 = 25 students

Number of ways of selecting 2 male out of 13 males = combination(13,2) = of selecting both students as men

Number of ways of selecting at 1 male and 1 female = combination(13,1)*combination(12,1)

this gives

combination(13,1)*combination(12,1) =

And number of ways of selecting 2 students out of 25 = combination(25,2) = ways

So, the required probability of selecting at least 1 male = (number of ways of 2 male+number of ways of selecting 1 male and 1 female)/(total number of ways of selecting 2 students out of 25 students)

setting the values, we get

Probability = (78+156)/300 = 39/50 = 0.7800

So, the required probability is 39/50