If the teacher picks a group of 3 at random, what is the probability that everyone in the group is a girl ?
+2208
There are 10 students in a class: 6 boys and 4 girls. If the teacher picks a group of 3 at random, what is the probability that everyone in the group is a girl ?
Probability first pick is a girl 4 / 10
Probability second pick is a girl 3 / 9
Probability third pick is a girl 2 / 8
Probability all three happening 4/10 • 3/9 • 2/8 = 24 / 720 = 1 / 30
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