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In this article
PI returns 3.14159265358979, accurate to 15 digits. It takes no arguments but still needs the brackets.
Syntax
=PI()Examples
Example 1
=PI()*(B2/2)^2Area of a round table from its diameter.
PI in practice
Where you will use it
- Area of circular land or pipes
- Volume of cylindrical tanks
- Circumference calculations
Worked example
Area of a circle = PI x r squared.
| Radius (m) | Formula | Result |
|---|---|---|
| 1 | =ROUND(PI()*A2^2,2) | 3.14 |
| 2.5 | =ROUND(PI()*A3^2,2) | 19.63 |
| 10 | =ROUND(PI()*A4^2,2) | 314.16 |
Results calculated in Excel.
Mistakes people make
| Mistake | What to do instead |
|---|---|
| Typing 3.14 | PI() gives full precision |
| Mixing diameter and radius | Area uses the radius (diameter/2) |
Related functions
POWER · RADIANS
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- 📗Practice workbook: Math & rounding24 tasks on realistic sales data — type your formula, the Check column turns green when it is right. Answers sheet included.⬇ XLSX · 35 KB
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