Usually expressed as a fraction, this is way of showing the relative size of two numbers,
as when 24/30 is written as 4/5, meaning 24 has as many groups of 4 as 30 has groups of

Urgent in guinea pigs, black fur (b) is dominant over white fur (b). cross a heterozygous (hybrid) black guinea pig with a homozygous (purebred) white guinea pig. complete a punnett square, identify the genotype(s), phenotype(s), and probability (% and fraction) that the offspring will be black and white?