Let A and B be too sets containing four and two elements respectively then the number of subsets of set `AxxB` having atleast 3 elements is

Explanation

Number of elements in set `A = 4`

Number of elements in set `B = 2`

Maximum elements that `AxxB` can have ` = 4xx2 = 8`

So, maximum number of subsets that `AxxB` can have `2^8`.

But, from these subsets, we have to find subsets that contains at least `3` elements.

So, we have to remove sets that have `0`, `1` and `2` elements.

So, required number of subsets ` = 2^8 - C(8,0)-C(8,1)-C(8,2)= 2^8 -1 - 8 - 28 = 2^8-37`

So, required number of subsets are `2^8 - 37`.