Solve common percentage questions, including a percentage of a value, a share of a total, and percentage change.
1. What is % of?
2. Value is what percentage of?
3. Percentage Increase / Decrease
Three Common Percentage Questions
The first panel calculates a percentage of a value by multiplying the value by the percentage divided by 100. The second divides a part by a total and converts the ratio to a percentage. The third compares a starting value with an ending value and reports the size and direction of the percentage change relative to the starting value.
Choose the correct starting value
Percentage change is undefined when the starting value is zero. A percentage increase or decrease is not the same as a percentage-point change, which is used when comparing two percentages.
Example and limitations
For a percentage-of-value question, 20% of 150 is 30. Percentage change compares the difference with the starting value, so the direction and reference value matter when interpreting an increase or decrease.