- Applying percentages to discounts and sales

Understanding Percentages in Discounts and Sales

Percentages are commonly used in shopping to calculate discounts and determine sale prices. Knowing how to apply percentages helps you make informed purchasing decisions and spot the best deals.

How to Calculate a Discounted Price

1. Find the discount amount:
   • Multiply the original price by the discount percentage (as a decimal).
   • Example: For a 20% discount on a $50 item, calculate 0.20 × $50 = $10.
2. Subtract the discount from the original price:
   • Original price - Discount amount = Sale price
   • Example: $50 - $10 = $40

Quick Method: Sale Price Formula

You can also calculate the sale price directly:

• Sale price = Original price × (1 - Discount percentage as a decimal)
• Example: $50 × (1 - 0.20) = $50 × 0.80 = $40

Tips for Applying Percentages

• Convert the percentage to a decimal by dividing by 100 (e.g., 25% becomes 0.25).
• For multiple discounts, apply each discount to the new price, not the original.
• Use a calculator or smartphone for quick calculations while shopping.

Practice Example

If a jacket costs $80 and is on sale for 30% off, what is the sale price?

• Discount amount: 0.30 × $80 = $24
• Sale price: $80 - $24 = $56

Learn More

For more on percentages and real-life math skills, visit the Khan Academy Percentages Guide.