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a family has five children. the probability of having a girl is 1/2. whats probability of having at leasr 4 girls g'

User Hailin Tan
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1 Answer

6 votes

Answer:

Probability of having at least 4 Girls

= 0.6875

Explanation:

Probability of having at least 4 Girls is 1-probability of having exactly 3 girls

Total number of children= 5 = N

Probability of having a girl p = 0.5

Probability of not having a girl q= 0.5

X= 3

Probability of at least 4 girls is given by

Probability= NCX(p)^x(q)^(N-x)

Probability = 5C3(0.5)^3(0.5)^(5-3)

Probability = 5C3(0.5)^3(0.5)^2

Probability= 5!/3!2!(0.5)^3(0.5)^2

Probability= 10(0.125)(0.25)

Probability= 0.3125

Probability of having at least 4 Girls

= 1- 0.3125

= 0.6875

User Damax
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