How many kinds of gametes will be expected from an individua

How many kinds of gametes will be expected from an individual with the genotype PpCcTTRr?

Please explain. :)

Solution

Number of different kinds of gametes = 2ⁿ

where n = number of heterozygous alleles (genes).

Pp, Cc and Rr are heterozygous and TT is homozygous. So, here n=3

2³ = 8