How to justify a/b x b/c = a/c?
well a/b * b/c = ab/bc, and since b/b= 1 you get 1a/c or just a/c :)
a/b times b/c is = ab/bcwhich can be written as a/c times b/banything over itself is 1 so b/b is onea/b times b/c = a/c
