The area of circle having radius 3cm is 28.27 cm², diameter 5cm is 19.63 cm², radius 8 ft is 201.06 ft², diameter is 113.1 cm², diameter 20 km is 314.16 km², diameter 15 mm is 176.71 mm² and radius 16 yd is 804.25 yd².
Given the radius and diamtere are (a) Radius (r) = 3 cm (b) Diameter (d) = 5 cm (c) Radius (r) = 8 ft. (d) Diameter (d) = 12 cm (f) Diameter (d) = 20 km (g) Diameter (d) = 15 mm (i) Radius (r) = 16 yd.
We will calculate the area of circle by using the formula A=πr² or π(d/2)².
(a) Radius (r)=3cm
The area of circle is
Area=π(3)²
Area =9π
Here, π=3.14, we get
Area =9×3.14
Area=28.27cm²
(b) Diameter (d)=5cm
The area of circle is
Area=π(5/2)²
Area =π(2.5)²
Area=6.25π
Here, π=3.14, we get
Area =6.25×3.14
Area=19.63cm²
(c) Radius (r)=8 ft
The area of circle is
Area=π(8)²
Area =64π
Here, π=3.14, we get
Area =64×3.14
Area=201.06ft²
(d) Diameter (d)=12cm
The area of circle is
Area=π(12/2)²
Area =36π
Here, π=3.14, we get
Area =36×3.14
Area=113.1cm²
(e) Diameter (d)=20km
The area of circle is
Area=π(20/2)²
Area =100π
Here, π=3.14, we get
Area =100×3.14
Area=314.16km²
(f) Diameter (d)=15mm
The area of circle is
Area=π(15/2)²
Area =56.25π
Here, π=3.14, we get
Area =56.25×3.14
Area=176.71mm²
(g) Radius (r)=16yd
The area of circle is
Area=π(16)²
Area =256π
Here, π=3.14, we get
Area =256×3.14
Area=804.25yd²
Hence, the area of circle having radius and diameter is radius 3cm is 28.27 cm², diameter 5cm is 19.63 cm², radius 8 ft is 201.06 ft², diameter is 113.1 cm², diameter 20 km is 314.16 km², diameter 15 mm is 176.71 mm² and radius 16 yd is 804.25 yd².
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