Question

The average of prime numbers between 1 and 20 is

Answer 1

there are a total of 8 prime numbers between 1 and 20. they are
2,3,,7,9,11,13,17 and 19
1 is a unique number. it is neither prime nor composite

Answer 2

Prime numbers from 1 to 20 = {2,3,5,7,11,13,17,19}
 
                                                = 8

Average of prime numbers = 2 + 3 + 5 + 7 + 11 + 13 + 17 + 19/ 8

                                              = 77 / 8

                                              = 9.625