Author note — to cover

Cover percentage profit and loss as a percentage of cost price: from cost and selling prices, finding a selling price to achieve a stated percentage profit, and losses handled as decreases. Stress the of-the-cost-price denominator. Recovering a cost price from a selling price is the reverse-problems group's work. Both tiers. (R9)

• Fluency — direct questions on percentage profit and loss, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).