Question

Let $A=\{1,2,3,...,10\}$ and $B=\{101,102,103,...,1000\}$. Then set $A$ and $B$ are

• A. Both finite sets
• B. Infinite and finite set respectively
• C. Both Infinite sets
• D. Finite and infinite set respectively

Answer 1

The correct option is A Both finite sets

$A=\{1,2,3,.....,10\}$ and $B=\{101,102,2013,...........,1000\}$

No. of elements in $A$ is $10$ and Number of elements in $B=1000-100=900$

$⟹|A|=10\text{and}|B|=900$

Thus, the cardinality of $A$ and $B$ are finite.

Hence, the are finite sets.