Question

How are 6/6 and 1 equivalent?

Answer 1

6/6 and 1 are equivalent because 6/6 has 6 parts of something and 6 prats are shaded which makes the whole thing shaded which makes it a whole, 6/6 = 1. 

Answer 2

Say you ate 6 slices of a cake that was cut into 6 you would have ate a whole cake.
So this means that 6 out of the 6 slice are gone, a whole cake has gone.