Question 1

How do I calculate percentage of a number?

Accepted Answer

Percentage of a number = Number × (Percentage / 100). For 25% of 80: 80 × 0.25 = 20. Convert percentage to decimal by dividing by 100, then multiply.

Question 2

How do I find what percent one number is of another?

Accepted Answer

Percentage = (Part / Total) × 100. For example, 20 is what percent of 80: (20 / 80) × 100 = 25%. Divide the part by the total, then multiply by 100.

Question 3

How do I calculate percent change?

Accepted Answer

Percent change = ((New - Original) / Original) × 100. Positive result is increase, negative is decrease. From 80 to 100: (100 - 80) / 80 × 100 = 25% increase.

Question 4

How do I calculate percentage increase?

Accepted Answer

New value = Original × (1 + Percentage/100). For $50 with 20% increase: $50 × 1.20 = $60. Add 1 to the decimal form of percentage and multiply.

Question 5

What is the difference between percent change and percent difference?

Accepted Answer

Percent change uses the original as base: (New-Old)/Old. Percent difference uses average as base: |A-B|/(A+B)/2. Use change when tracking growth over time, difference when comparing two unrelated values.

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