Choice B is the correct answer. Let $c$ = pounds of Colombian beans.

Equation: $\frac{8(15) + 12c}{15 + c} = 10$

Step 1: Multiply both sides by $(15 + c)$: $120 + 12c = 10(15 + c)$$120 + 12c = 150 + 10c$$2c = 30$$c = 15$

Solution: 15 pounds of Colombian beans

Verification: $\frac{8(15) + 12(15)}{15 + 15} = \frac{120 + 180}{30} = \frac{300}{30} = 10$ ✓

💡 Strategic Tip: Average price = total value ÷ total weight.

**Other choices fail verification.