What is a prime number between 10 and 20?

1 Answer
May 22, 2016

The numbers #11#, #13#, #17# and #19# are all prime numbers between #10# and #20#.

Explanation:

A prime number is a number that is only divisible by itself and #1#.

To say that a number is even is to say that it is divisible by #2#. As a result, the only even prime number is #2# itself.

So the only possibilities to consider are the odd numbers between #10# and #20#, namely:

#11#, #13#, #15#, #17#, #19#

Of these, all are prime except #15#:

#15# is divisible by #15#, #5#, #3# and #1#, so is not a prime number.