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A certain family consists of a mother, father, and 4 girls. The woman is pregnant with a fifth child. What is the probability that the 5th child is agirl? Before the first birth, what was the probability that the woman would give birth to 5 girls in a row?

User Sergei Krivosheenko
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1 Answer

12 votes
12 votes

The probability that the 5th child is a girl = 1/2

Before the first birth, the probability that the woman would give birth to 5 girls in a row = 0.03125

Step - by - Step expalanation

What to find?

• The probability that the 5th child is a girl.

,

• Before the first birth, the probability that the woman would give birth to 5 girls in a row.

Probability = required outcome / all possible outcome.

For the first part of the question, the 5th child could either be a boy or girl.

So, all possible outcome = 2 and the required outcome = 1

Hence, the probability that the fifth child is a girl = 1/2

For the second part of the question,

Before, the first birth, the probabilty that the woman would give birth to 5 girls in a row will simply =(probability of given birth to a girl)^no. of times she will give birth.

That is;


((1)/(2))^5


=(0.5)^5


=0.03125

User Qudus
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