Answer:
Phenotype ratio= 3 purple: 1 white
Genotype ratio= 1 PP: 2 Pp: 1 pp
Explanation:
Let's assume that the dominant allele "P" impart purple color to the flowers while the recessive allele "p" is responsible for the white color of flowers. The genotype of the true breeding purple-flowered plant would be "PP" and that of the true breeding white-flowered plant would be "pp".
A cross between them would produce F1 progeny with genotype "Pp". All the F1 progeny would have purple flowers. A cross between two F1 (Pp x Pp) would obtain F2 generation in the following ratios:
Phenotype ratio= 3 purple: 1 white
Genotype ratio= 1 PP: 2 Pp: 1 pp