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LampPro Tip 1/3
Circle BasicsPlay
A radius is essential in geometry for calculating area and circumference of a circle. Find the area of a circle by using the radius in the formula Area = πr^2.
LampPro Tip 2/3
Measure TwicePlay
Always double-check the length of a radius, as even a small error changes the circle size significantly. SlideShe carefully measured the radius again before cutting the round cake board.
LampPro Tip 3/3
Not a DiameterPlay
Do not confuse radius with diameter; the radius is half the length of the diameter. SlideThe diameter is twice the radius, so if the radius is 4 cm, the diameter will be 8 cm.