1. Problem (c): A dining room set is advertised with a 20% discount, and the discounted price is 75000. Calculate the original price before discount. 2. Formula: The discounted price is given by $$\text{Discounted Price} = \text{Original Price} \times (1 - \text{Discount Rate})$$ where the discount rate is 20% or 0.20. 3. Let the original price be $x$. Then: $$75000 = x \times (1 - 0.20) = x \times 0.80$$ 4. Solve for $x$: $$x = \frac{75000}{0.80} = 93750$$ 5. Explanation: To find the original price, divide the discounted price by 0.80 because the price after a 20% discount is 80% of the original price. 6. Final answer: The original price before discount is $93750.