Question

Coat color in one breed of mice is controlled by incompletely dominant alleles so that yellow and white are homozygous, while cream is heterozygous. The cross of two cream individuals will produce


Answer: Equal numbers of white and yellow mice, with 2X as many creams as the other two colors


I know the answer, but why is it that?

Answer 1

http://staff.jccc.net/pdecell/transgenetics/monohybrid1.html
go through this link
Incompletely dominant means when a pair of genes control a phenotipic expression of a particular trait, None is considered completely dominant.
IE: In the given case, Genes controlling white be Cw and yellow be Cy both are incompletely dominant over each other.
When 2 heterozygous mice with genotype CwCy are crossed offspring are CwCw, CwCy, CwCy,CyCy

IE:
1 white with CwCw
2 Cream with CwCy
1 Yellow with CyCy
both traits are expressed in a cream mice, giving a mixture of white and Yellow colour---->cream.