WAEC Mathematics 2025 Paper

Concept:The selling price includes the original cost price plus the profit earned on it. A profit of $50\%$ means the selling price is $150\%$ of the cost price.Explanation:Let the cost price be $CP$.Profit is $50\%$ of $CP$, which is $0.5 \times CP$.Selling price is the total of cost price and profit, so $SP = CP + 0.5CP$.This gives $SP = 1.5CP$.The dealer sold the drinks for $\text{NGN 600.00}$, so $1.5CP = 600$.Solving for the cost price: $CP = \frac{600}{1.5}$.Therefore, $\text{CP} = \text{N}400.00$.As a check: $50\%$ of $\text{N400.00}$ is $\text{N}200.00$, so selling at $\mathrm{N}400 + \mathrm{N}200 = \mathrm{N}600.00$ gives the correct profit.Answer:The dealer paid $\text{NGN }400.00$ for the drinks.Correct option: A. $\text{N}400.00$