1985 AHSME Problem 8

Let a, a', b, and b' be real numbers with a and a' nonzero. The solution to ax+b=0 is less than the solution to a'x+b'=0 if and only if

\mathrm{(A)\ } a'b<ab' \qquad \mathrm{(B) \ }ab'<a'b \qquad \mathrm{(C) \ } ab<a'b' \qquad \mathrm{(D) \ } \frac{b}{a}<\frac{b'}{a'} \qquad

\mathrm{(E) \ }\frac{b'}{a'}<\frac{b}{a}

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.