A non-haemophilic couple was informed by their doctor that there is possibility of a haemophilic child being born to them. Draw a checker board and find out the percentage of possibility of such a child among the progeny.

Haemophilia is a sex linked recessive disease which shows its transmission from unaffected carrier female to some of the male progeny.



So, the percentage of their progeny being affected with haemophilia is 25%. (50% of sons are haemophilic and 50% of daughters are unaffected carriers).


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