*this is based on the assumption that parent two is homo_zygous dominant.
If a hetero_zygous and a homo_zygous dominant parent are crossed:
Genotypic Ratio
WW: Ww
1 : 1
Phenotypic Ratio
white : purple
[1 : 0] or [100% : 0%]
100 will have a white colour while 0 will have a purple colour.