1. **State the problem:** Solve the expression $5.5 - 4 \times 3$. 2. **Recall the order of operations:** According to the order of operations (PEMDAS/BODMAS), multiplication is performed before subtraction. 3. **Calculate the multiplication first:** $$4 \times 3 = 12$$ 4. **Substitute back into the expression:** $$5.5 - 12$$ 5. **Perform the subtraction:** $$5.5 - 12 = -6.5$$ 6. **Final answer:** $$\boxed{-6.5}$$