biology - Genetic probability
posted by Axel .
Black coat colour in Labrador Retrievers is produced by the dominant B allele. Brown labs are homozygous recessive (bb). Duke, a black male, whose mother was brown, is mated with Shadow, a black
female, who in a previous mating with another father produced brown offspring. What is the probability
that when Duke and Shadow are mated…
a. Their first pup is brown?
b. They have 3 male pups and at least one is black?
c. They have 3 black pups (regardless of sex)?
Please help me, I have answers but I am completely unsure if they are right. My answers are a)1/4 chance, b) 7/8 chance, and c)3/4. Please show how you get your answers so I know what I am doing wrong. Please and thank you