Question

The cardinal number of the set $A=\{1,2,2,3,4,5,5,6,6,7,7,8\}$ is .

• A. $8$
• B. $7$
• C. $12$

Answer 1

The correct option is A $8$

Given set $A=\{1,2,2,3,4,5,5,6,6,7,7,8\}$.
Now, since we know cardinal number is the number of distinct elements of the set which is $8.$

Hence, the cardinal number of the set $A$ is $8.$