Answer:
<h2> (1/4 * 60)
</h2><h2>The probability. that child will have extra fingers and toes are = 0.15
</h2>
Explanation:
As given; extra fingers and toes are caused by a recessive trait.
Penetrance= 60%.
Parents are heterozygous, assume Ff and Ff
F is dominant over f, and ff are homozygous recessive.
Ff crossed with Ff
Progeny are; FF, Ff, Ff and ff.
ff are homozygous recessive, as given that extra fingers and toes are caused by a recessive trait, so 1/4 will show the trait.
But according to 60% penetrance the trait will occur in = (1/4 * 60) =15% or 0.15 progeny will show the trait
.
The probability, that child will have extra fingers and toes are = 0.15
