Solve the inequality
\(\frac{r}{6}\) ≤ 3
Ar ≥ 18
Br ≤ 18
Cr ≤ 1/2
Dr ≤ 9
\(\frac{r}{6}\) ≤ 3
Ar ≥ 18
Br ≤ 18
Cr ≤ 1/2
Dr ≤ 9