Question

What is the sum of smallest odd prime number and largest prime number smaller than $20$?

Answer 1

The smallest prime number less than $20$ is $2$.

The largest prime number less than $20$ is $19$.

The sum of smallest odd prime number and largest prime number smaller than $20$ $=2+19$

$=21$

Hence, the sum of smallest odd prime number and largest prime number smaller than $20$ is $21$.