Set A has 4 elements
Set B has 2 elements
Number of elements in set (A x B) = 4 x 2 = 8
Total number of subsets of (A x B) = 28 = 256
Number of subsets having 0 elements = 8c0 = 1
Number of subsets having 1 element each = 8c1 = 8
Number of subsets having 2 elements each = 8c2= 8!/(2!6!)=8*7/2=28
Number of subsets having at least 3 elements
= 256 - 1 - 8 - 28 = 256 - 37 = 219
So the answer is 219.
