7 and 13, yes
15, no.
The prime numbers between 6 and 15 are: 7, 11, 13
The numbers 5, 7, 11 and 13 are prime.
Prime numbers from 1 to 15 are 2, 3, 5, 7, 11 and 13.
They are: 5 7 11 and 13
2 3 5 7 11 13 15
7, 11, 13
2, 3, 5, 7, 11 and 13 are prime.
The prime numbers are: 2 3 5 7 11 and 13 so therefore as a fraction of 15 it is 6/15 or 2/5 simplified
They are: 5, 7, 11 and 13
Three: 7 11 13.
There are 6 prime numbers between 1 and 15: 2 3 5 7 11 13.
2 3 5 7 11 13