1. The problem is to evaluate the expression $120 \div (-15) - 6 \times (-3)$.\n\n2. We use the order of operations (PEMDAS/BODMAS): first division and multiplication from left to right, then subtraction.\n\n3. Calculate the division: $$120 \div (-15) = -8$$\n\n4. Calculate the multiplication: $$-6 \times (-3) = 18$$\n\n5. Substitute these values back into the expression: $$-8 - (-18)$$\n\n6. Subtracting a negative is the same as adding: $$-8 + 18 = 10$$\n\n7. Therefore, the final answer is $10$.