Lesson 6
Percentage Decrease
Calculate percentage decreases and discounts.
- intermediate
Formula
% Decrease = ((Original - New) ÷ Original) × 100
📚 Percentage Decrease
A percentage decrease (or discount) tells you how much a value has dropped compared to its original amount.
Example: Price dropped from $80 to $60
💡 Pro Tip: Finding Sale Price
If something is 30% off, you pay 70% of the original price.
Sale Price = Original × (100 - Discount%) ÷ 100
Frequently Asked Questions
How do I calculate a percentage decrease?
Divide the decrease by the original value and multiply by 100: from 80 to 60 is 20 ÷ 80 × 100 = 25%.
How do I subtract a percentage from a number?
Multiply by 1 minus the percentage as a decimal: 30% off $90 is $90 × 0.70 = $63.
Practice
Work each one out, then check yourself.
A $120 jacket is now $90. What's the percentage discount?
Hint: Find the discount amount ($30), divide by original ($120), multiply by 100
Show answer
25
Final Quiz
0/3
Test what you learned. Pick the correct answer for each question.
A $80 jacket is 25% off. Discount price?
$80 × (1 − 0.25) = $60.
A laptop dropped from $1,200 to $900. Percentage decrease?
($1200 − $900) ÷ $1200 × 100 = 25%.
Which discount saves more on a $200 item: 30% off, or $50 off?
30% of $200 = $60, more than $50.