Question

A={3,5,7} B={7,8}. Find the number of relations from A to B

Answer 1

64

Given:

Set A = {3, 5, 7}

Set B = {7, 8}

Number of elements in Set A = 3

Number of elements in Set B = 2

To Find:

Number of relations from A to B.

Calculating:

Formula used for calculating the number of subsets of A x B:

= No of elements in set A x No of elements in set B

Substituting the values:

= 3 x 2

= 6

Formula that is used to calculate the number of relations:

= $2^{n}$

Here, n is the number of subsets in A x B.

Putting the value of n in this formula we get:

= $2^{6}$

= 2 × 2 × 2 × 2 × 2 × 2

= 64

Therefore, the number of relations from A to B is 64.