Topic Details (Notes format)

How to Calculate the Area of a Circle

Subject: Mathematics

Book: Maths Mastery

The area of a circle is given by the formula A = πr², where r is the radius—the distance from the center to the circumference. If you have a circle with radius 5 cm, its area is π × 5² = 25π cm². In practical terms, you might need to measure the space a circular rug covers or the cross-sectional area of a circular pipe. Knowing how to apply A = πr² is foundational in geometry, engineering, and architecture. Pairing this knowledge with circumference or volume formulas further expands your capability to handle circular shapes in diverse projects and daily scenarios.

Practice Questions

If a square has a perimeter of 64 cm, what is its area?

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The simple interest on Rs. 4000 at 5% per annum for 2 years is:

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If a:b = 7:9 and b:c = 5:6, what is a:c?

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