If you want to reduce a fraction to lowest terms, you don't cancel
prime factors. You cancel common factors.
The factors of 13 are 1 and 13 .
The factors of 24 are 1, 2, 3, 4, 6, 8, 12, and 24 .
The only common factor of 13 and 24 is ' 1 '.
So the fraction 13/24 is already in lowest terms,
and can't be reduced further.
