1. Finding the Percentage of a Value (X% of Y)
To find a percentage of a number, convert the percentage into a decimal by dividing by 100, then multiply by the total. For example, to find 15% of $80: (15 ÷ 100) × 80 = $12.
2. Calculating Retail Discounts and Sales Tax
For discounts: Multiply the original price by (1 - discount percentage ÷ 100). For example, a $120 jacket with a 25% discount costs: 120 × 0.75 = $90.
For sales tax: Multiply the pre-tax amount by (1 + tax rate ÷ 100). For example, a $50 purchase with 8% sales tax costs: 50 × 1.08 = $54.
Step-by-Step Tutorial
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Frequently Asked Questions
How do I calculate percentage increase between two numbers?
Subtract the old number from the new number, divide by the old number, and multiply by 100: [(New - Old) ÷ Old] × 100.
Does this tool work on mobile?
Yes! The calculator is fully responsive and works offline on any smartphone.