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How do you find the area of the circle if you only know the circumference?. For Example. A circle has a circumference of 37.68 cm. What is the area of the circle?. In this lesson you will learn how to find the area of a circle by using the measure of the circumference.
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How do you find the area of the circle if you only know the circumference? For Example A circle has a circumference of 37.68 cm. What is the area of the circle?
In this lesson you will learn how to find the area of a circle by using the measure of the circumference.
Area of a Circle = πr2 Circumference of a Circle= πdor 2πr
Divide the diameter by 2 to find the radius. Find the area of a circle with a diameter of 6 cm. Wrong Correct A = π(6cm)2 A = π(3cm)2 A = 36πcm2 A = 9πcm2
A playground in the shape of a circle has a circumference of 18π yards. What is the area of the playground? C = 18π yds. 18 yds C = πd D = 18 yds
Diameter = 18 yards Radius = 9 yards 18 yds Area = π(9 yds)2 9 yds Area = 81πyds2
A circle has an approximate circumference of 37.68 cm. If 3.14 was used for pi, what is the area of the circle? C = πd 37.68cm = 3.14d 37.68cm = 3.14d 3.14 3.14 d = 12 cm
A circle has an approximate circumference of 37.68 cm. If 3.14 was used for pi, what is the area of the circle? d = 12 cm r = 6 cm A = 3.14(6cm)2 A = 3.14(36cm2) A = 113.04 cm2
In this lesson you have learned how to find the area of a circle by using the measure of the circumference.
The circumference of a circle is 10π. What is the area of the circle?
The circumference of the Earth is approximately 25,000 miles. If you were to dig a hole to the center of the Earth, how long would the tunnel be? Explain how you found your answer.
The Redwood trees in California are said to have trunks so large that a car could fit in them. Estimate the circumference of the Redwood tree. Use your estimate to then find the area of the trunk if the tree was cut down. Explain your reasoning.
The circumference of a circle is 12.56 ft². If 3.14 was used to approximate pi, what is the area of the circle? A circle has a circumference of 9πmeters. Find the area of the circle.