What is 54 over 243 in simplest form?

To simplify 54 over 243, you first find the greatest common factor (GCF) of both numbers, which is 9. Divide both the numerator and denominator by 9 to get 6 over 27. Then, simplify further by dividing both numbers by the GCF again to get the simplest form, which is 2 over 9.