Question

t is commonly assumed that babies are equally likely to come as either a boy or a girl. This is not true. Actually, about 51.3% of all babies are boys. If a family has two children (not twins), what is the probability they have one boy and one girl?

Answer 1

The probability they have one boy and one girl = 0.50 = 50 %

Explanation:

Here the family has two children, we need to find what is the probability they have one boy and one girl.

Probability for babies are boys = 51.3% = 0.513

Probability for babies are girls = 1 - 0.513 = 0.487

The probability they have one boy and one girl = 1 - probability that they have two boys - probability that they have two girls

The probability they have one boy and one girl = 1 - 0.513² - 0.487² = 0.499 = 0.50

The probability they have one boy and one girl = 0.50 = 50%