If a, b, c, and f are four nonzero numbers, then all of the following proportions are equivalent except:

Question

If a, b, c, and f are four nonzero numbers, then all of the following proportions are equivalent except:

A) a/f = b/c

B) f/c = b/a

C) c/a = f/b

D) a/c = b/f

E) af/bc = 1/1

Answer 1

These are proportions. One ratio equal to another ratio.

You can flip both fractions without altering the proportion.

You can cross multiply.

You can switch one set of variables cross-wise or both sets.

 

If you write all the options and perform all the permutations, you will see that   a/f = b/c is not equivalent to the other four proportions