Annulus area
Annulus area: use outer radius, inner radius. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
A = π(R²−r²)
Variables & units
- Outer radius
- m · minimum 0, maximum 1000000000000
- Inner radius
- m · minimum 0, maximum 1000000000000
Worked example
Radii 5 and 3 give 16π square units.
Assumptions
Both circles must share a centre.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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