Percent: One Template for Part, Whole and Rate
Every basic percent item uses one template: Part = Rate × Base. Learn to spot the part, the whole and the rate, convert the percent, and solve for the missing one.
What it is
Percent means "per hundred". 30% means 30 out of every 100. A percent is simply a fraction with 100 at the bottom: 30% = 30/100.
Every basic percent problem has three numbers:
- the whole (also called the base): the total amount;
- the part (also called the percentage): a piece of that total;
- the rate: the percent that tells how big the part is compared with the whole.
They are always linked by one template: Part = Rate × Base. Two of the three are given; you find the third.
Why it matters on the exam
Percent is one of the most frequent topics in the Numerical Ability part of both the Professional and Sub-Professional exams. It also returns in later topics: percent change, discounts, interest and data interpretation all use the same template.
At work, percent is everywhere: passing rates, budget shares, tax, collection targets and survey results.
- 13.5
- 75
- 135
- 150
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Read moreIn the full lesson
- How to recognize it on the test
- What to look for (5 checks)
- All 4 rules and tools
- 3 worked examples, every step explained
- 6 common mistakes and how to fix them
- 3 exam techniques
- Remember: 5 key points
- Practice questions with explanations, and your progress saved
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