To find the fractions simplest form, we first need to solve for the GCF of the two numbers, 28 & 36. We do this by finding the prime factors.
28=7*
2*236=3*3*
2*2
The numbers have the prime factors of 2*2 in common, therefore the GCF is 4. (2*2=4)
28/4=7 36/4=9

Answer=7/9