Percentage Change
Calculate increases and decreases instantly.
Core Concepts
Calculating a price increase (tax, tip) or decrease (discount) is easy if you break it down. First find the percentage amount, then add or subtract it from the original number.
Increase (+)
New Value = Original + Percentage Amount
Example: Increase 50 by 10%.
10% of 50 is 5.
50 + 5 = 55.
Decrease (-)
New Value = Original - Percentage Amount
Example: Decrease 50 by 10%.
10% of 50 is 5.
50 - 5 = 45.
Solved Examples
Example 1: Increase 80 by 20%
Question: Increase 80 by 20%.
• Step 1: Find 10% of 80 = 8.
• Step 2: 20% is double, so 16.
• Step 3: Add to original: 80 + 16 = 96.
• Answer: 96.
Example 2: Decrease 60 by 5%
Question: Decrease 60 by 5%.
• Step 1: Find 10% of 60 = 6.
• Step 2: 5% is half, so 3.
• Step 3: Subtract from original: 60 - 3 = 57.
• Answer: 57.
Example 3: Increase 200 by 1%
Question: Increase 200 by 1%.
• Step 1: Find 1% of 200 = 2.
• Step 2: Add to original: 200 + 2 = 202.
• Answer: 202.
Example 4: Decrease 100 by 25%
Question: Decrease 100 by 25%.
• Step 1: 25% is a quarter. Quarter of 100 is 25.
• Step 2: Subtract: 100 - 25 = 75.
• Answer: 75.
