Math9-12+
Calculating Sale Prices and Original Costs Practice
By Jessica N.
A practice set of 10 problems plus a worked exemplar that helps 9th graders find sale prices after 10%, 15%, 20%, and 50% discounts and work backward to original costs. Students build percent and decimal multiplier skills through real-world shopping contexts, with the exemplar modeling the steps before they work independently.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-40 minute independent or partner practice block after a brief mini-lesson on converting percents to decimal multipliers (for example, 20% off means paying 0.80 of the price).
- Discussion question: Why does a 50% discount give the same result as cutting the price in half, and how could you check a sale price using estimation?
- Scaffold for struggling readers: Have them complete the exemplar aloud with you, then solve one problem with a calculator-free multiplier table before moving on.
- Extension for advanced students: Ask them to compare two back-to-back discounts (for example, 20% then 15% off versus 35% off) and explain why the results differ.
- Estimated time: about 35 minutes for all 10 problems, plus 5 minutes for the exemplar review.
Math9-12+
Calculating Sale Prices and Original Costs Practice
By Jessica N.
A practice set of 10 problems plus a worked exemplar that helps 9th graders find sale prices after 10%, 15%, 20%, and 50% discounts and work backward to original costs. Students build percent and decimal multiplier skills through real-world shopping contexts, with the exemplar modeling the steps before they work independently.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-40 minute independent or partner practice block after a brief mini-lesson on converting percents to decimal multipliers (for example, 20% off means paying 0.80 of the price).
- Discussion question: Why does a 50% discount give the same result as cutting the price in half, and how could you check a sale price using estimation?
- Scaffold for struggling readers: Have them complete the exemplar aloud with you, then solve one problem with a calculator-free multiplier table before moving on.
- Extension for advanced students: Ask them to compare two back-to-back discounts (for example, 20% then 15% off versus 35% off) and explain why the results differ.
- Estimated time: about 35 minutes for all 10 problems, plus 5 minutes for the exemplar review.