What are the chances of two parents who carry the gene for albinism (an autosomal recessive disorder) having a child without albinism?

Let the recessive allele for albinism be ar and dominant gene be ad
since it is autosomal, no link with sex-linked chromosomes. 
both parents are carriers, meaning that each have one allele for albinism
their genotypes would be: arad, arad×arad
possible genotypes of children: arar, arad, arad and adad
thus 3 out of 4 children do not have albinism. chances are 75%