Countdown to Exams - Day 56 - Area and Circumference (Circles)
In today's countdown, we focus on the topic of area and circumference of circles. As with all area formulae, you will need to memorise these for the area and circumference of a circle. Make sure you are dealing with the element of the circle (diameter or radius) before you substitute into the formula. Always double check your calculations to see if your answer is reasonable (circumference is about three times the length of the diameter).
When calculating sector areas and arc lengths remember to work out the proportion of the circle you are dealing with (amount of degrees given over 360). Then it is a case of using the original formulae to calculate your answer.
In the video below, Matt will guide you through calculating area and circumference of circles and then show you how to find the proportion of the circle for sectors and arcs.
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