Two heterozygous parents () have three children. What is the probability that exactly one child is ?
Answer and explanation
Correct answer: D.
- Step 1: Probability that a child is is and not is .
- Step 2: There are ways to choose which child is .
- Step 3: .
Answer
.
Why not the others: : is the probability for a single child. : is the probability that exactly two are . : is the probability that all three are .
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