Question

Let S = {1, 4, 6, 9}

Determine the total number of sets B that satisfy 1∈B and B⊆S. (Be able to list all possible sets B.)

Answer 1

There are 8 sets B that satisfy the conditions.

Explanation:

We have to find the total subsets of S that have 1 as an element.

Subsets B with one element: {1}

Subsets with two elements: {1,4}, {1,6}, {1, 9}

Subsets with three elements: {1,4,6}, {1,4,9}{1,6,9}

Subsets with four elements: {1,4,6,9}

Therefore, B = {1, {1,4}, {1,6}, {1, 9}, {1,4,6}, {1,4,9}, {1,6,9}, {1,4,6,9}}