Area of a Circle
Definition of Area of a Circle
Area of a Circle is the amount of space occupied by the circle.
More About Area of a Circle
Area of a circle of radius r is given by = πr2.
Examples of Area of a Circle
Area of a circle = πr2 = π(6)2 = 36π cm2 or 113.04 cm2. [Use π = or 3.14]
Video Examples: Area of a Circle
Solved Example on Area of a Circle
Find the area of a circle, if the diameter of the circle is 4 cm. [Use π = 3.14]
Choices:A. 25.12 cm2
B. 6.28 cm2
C. 12.46 cm2
D. 12.56 cm2
Correct Answer: D
Step 1: Let r be radius of the circle.
Step 2: Diameter of the circle = 2r
Step 3: 4 = 2 × r.
Step 4: r = 4/2 = 2 cm
Step 5: Area of the circle = π × r2 [Formula.]
Step 6: Area of the circle = 3.14 × 4 = 12.56 [Substitute the values of π and r.]
Step 7: So, the area of the circle is 12.56 cm2