In ligers stripes are dominant over solids if two heterozygous ligers mate what is the chance of their baby liger having stripes and the chance of their baby liger having solids

Guinea pig coat color is determined by a single gene. the allele for black coat color is dominant to brown. in a cross between twoblack-haired guinea pigs, 20 offspring are born. if both parents were heterozygous, probability would predict that approximately howmany of the 20 offspring would have brown hair?