Question

A carrier haemophiliac woman marries a haemophiliac man. What are the chances for her progeny to be haemophiliac?
(a) 25%
(b) 50%
(c) 75%
(d) 100%

Answer 1

(b) 50%

If a carrier haemophiliac woman marries a haemophiliac man, their progeny will have a 50% chance of becoming haemophiliac, 25% chance of being carriers and 25% chance of being normal.