A snapdragon with pink flowers with the genotype Rr is mated with a snapdragon with red flowers with the genotype RR. What is the possibility of obtaining a flower with a heterozygous genotype?

The possibility of obtaining a heterozygous flower is %.

50%

Since one of the parents is homozygous for RR, we absolutely know that parent will be contributing the R allele. And in order to get a heterozygous offspring, it has to have the genotype Rr. In order for the r allele to be contributed it has to come from the genotype Rr parent. And for that parent, half of its offspring will be given the R allele and half the r allele. So there's a 1/2 or 50% probability of getting a heterozygous flower from those 2 parents.