A class has 11 boys, 9 girls. Two students will be selected at random to serve on committee. What's probability that both will be girls?

Expert Answers

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Given that the number of boys and girls in a class is as follows:

Number of boys = 11

Number of girls = 9

Then we conclude that the total number of students in the class= 20 students.

Then, the probability of choosing a girl = number of girls. total number of students in the class = 9/20

The probability of choosing the 2nd girl = number of remaining girls / number of all students minus the chosen girl = 8/19

Then , the probability of choosing two girls is :

The probability of choosing 2 girls = 9/20 *  8 /19

                                                 = 72/380

                                                 = 18/ 95

Then the probability of choosing 2 girls = 18/95                                     

Approved by eNotes Editorial Team
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