### A dealer offers a cash discount of 20% and still makes a profit of 20%, when he further allows 16 articles to a dozen to a particularly sticky bargainer. How much percent above the cost price were his wares listed?

A. 100% B. 80% C. 75% D. $66 \frac{2}{3} \%$ Answer: Option A
Let the ware listed x% above C.P. and Let C.P. be W According to question, $\mathrm{W} \times\left(1+\frac{\mathrm{x}}{100}\right) \times \frac{4}{5} \times 12 \times \frac{1}{16}=\mathrm{W} \times \frac{6}{5}$ Solving we get x = 100 Thus his wares were listed 100% above C.P.