GCSE Maths Practice: circle-properties

Question 8 of 10

This question teaches the formula for circumference in terms of radius.

‹ ›

\( \begin{array}{l}\text{Write the formula for the circumference of a circle in terms of the radius } r.\end{array} \)

Choose one option:

Multiply 2 by π and the radius to find the circumference.

The circumference of a circle is the distance around its boundary. It is calculated as 2πr, where r is the radius, or equivalently πd, where d is the diameter. Understanding this formula is essential for solving perimeter problems, real-life applications, and further geometry topics. Students should practise calculating circumference with different radii and diameters. Mastery ensures accuracy in both theoretical and practical geometry problems. Visualising the radius and wrapping it around the circle helps understand why 2πr is used.