Types of gametes = 2n
n = number of heterozygotes considered i.e., monohybrid cross (n = 1), dihybrid cross (n = 2), trihybrid cross (n = 3) and so on. AABBCC×aabbcc is a trihybrid cross, therefore, different types of gametes are = 2n n=3=(2)3=2×2×2=8 .