The probability that a boy is born with Down's syndrome is p, 0

The probability that a baby born with Down's syndrome is a boy is .

Step-by-step explanation:

The probability of a baby born being a boy (B) or a girl (G) is same, i.e.

P (B) = P (G) = 0.50.

The probability of a boy is born with Down's syndrome is, P (D|B) = p.

The probability of a girl is born with Down's syndrome is, P (D|G) = q.

The law of total probability states that:

Use this law to compute the probability of a baby born with Down's syndrome as follows:

The conditional probability of an event X given that another event Y has already occurred is:

Compute the probability that a baby born with Down's syndrome is a boy as follows:

Thus, the probability that a baby born with Down's syndrome is a boy is .

step-by-step explanation: