What are the prime numbers between 20-30?

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Answer 1 · 2017-05-03T01:11:58

See the solution process below:

The numbers between 20 and 30 are:

#21, 22, 23, 24, 25, 26, 27, 28, 29#

Even numbers, other than #2# are not prime because by definition of being even they are divisible by #2#. This then leaves:

#21, 23, 25, 27, 29#

#21 = 3 xx 7# - not prime

#25 = 5 xx 5# - not prime

#27 = 3 xx 9# - not prime

This leaves:

#23, 29#

For both of these numbers the only numbers they are evenly divisible by is #1# and themselves.

Therefore, #color(red)(23)# and #color(red)(29)# are the prime numbers between 20 and 30.