Explanation

To solve this question, plug in the answers. In choice (D), if Ben, B, sold 6500 copies and $B = \frac{5}{6} \times R$ then $6500 = \frac{5}{6} \times R$, so Regina, R, sold 7800 copies, thus giving a difference of 7800 − 6500 = 1300. Since this is too small, eliminate choices (D), (E), and (F) and try larger numbers.

In choice (C), if B = 9000, then $9000 = \frac{5}{6} \times R$, so R = 10,800, thus giving 10,800 − 9000 = 1800; since this is bigger than 1500, keep choice (C).

In choice (B), if B = 11,244, then $11,244 = \frac{5}{6} \times R$, so R = 13,492.8 copies; eliminate choice (B), as it is impossible to sell a fraction of an album.


In choice (A), if B = 12,000, then $12,000 = \frac{5}{6} \times R$, so R = 14,400 and 14,400 − 12,000 = 2400. Since this is bigger than 1500, keep choice (A).

The correct answers are choices (A) and (C).