Find the probability of at least 2 girls in 10 births.Assume that male and female births are equally likely and that the births are independent events.
A)0.989
B)0.011
C)0.044
D)0.1
E)0.945

Question

Quizplus · Accepted Answer

The probability of at least 2 girls in 10 births can be found by subtracting the probability of getting 0 or 1 girl from 1. The probability of a girl or boy being born is 0.5 each. For 0 girls, the probability is (0.5)^10. For 1 girl, it's 10*(0.5)^10. Adding these and subtracting from 1 gives 1 - [(0.5)^10 + 10*(0.5)^10] = 0.989.

Find the Probability of at Least 2 Girls in 10