Percent of a Number Examples in Math
Start with the recap, study the fully worked examples, then use the practice problems to check your understanding of Percent of a Number.
This page combines explanation, solved examples, and follow-up practice so you can move from recognition to confident problem-solving in Math.
Concept Recap
Calculating a given percentage of a quantity by converting the percent to a decimal (or fraction) and multiplying.
25\% of 80 means 'one quarter of 80.' Convert 25\% to 0.25 and multiply: 0.25 \times 80 = 20.
Read the full concept explanation →How to Use These Examples
- Read the first worked example with the solution open so the structure is clear.
- Try the practice problems before revealing each solution.
- Use the related concepts and background knowledge badges if you feel stuck.
What to Focus On
Core idea: Percent of a number is just fraction-of-a-number with the fraction being 'out of 100.'
Common stuck point: Students confuse 'percent of' with 'percent is'—15% of 200 is 30, but 30 is what percent of 200?
Sense of Study hint: Replace the percent sign with 'divided by 100' and the word 'of' with a multiplication sign, then compute left to right.
Worked Examples
Example 1
easySolution
- 1 Convert the percentage to a decimal: 35\% = 0.35.
- 2 Multiply: 0.35 \times 140 = 49.
- 3 Alternatively: \frac{35}{100} \times 140 = \frac{35 \times 140}{100} = \frac{4900}{100} = 49.
Answer
Example 2
mediumPractice Problems
Try these problems on your own first, then open the solution to compare your method.
Example 1
easyExample 2
hardBackground Knowledge
These ideas may be useful before you work through the harder examples.