In fruit flies eye color is a sex linked trait where red eyes are dominant to the white eye phenotype. If a red eyed male is crossed with a female who carries the white eye gene, what is likelihood of having an offspring with white eyes?
By making a monohybrid punnet square you come out with these pairs of Alleles: Ee, ee,ee,and Ee. Which will give you 1/2 probability to get white eyes or even red eyes.