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Mensuration of a Circle: Area and Circumference



A circle has radius 18 inches. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 182 = 1017.88 square inches
Perimeter of the circle = 2Π x Radius = 2Π x 18 = 113.1 square inches

A circle has radius 4 cm. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 42 = 50.27 square cm
Perimeter of the circle = 2Π x Radius = 2Π x 4 = 25.13 square cm

A circle has radius 9 m. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 92 = 254.47 square m
Perimeter of the circle = 2Π x Radius = 2Π x 9 = 56.55 square m

A circle has radius 14 units. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 142 = 615.75 square units
Perimeter of the circle = 2Π x Radius = 2Π x 14 = 87.96 square units

A circle has radius 11 inches. What is the area and the perimeter (circumference) of the circle?


You are given a circle with a circumference 6.28 inches. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 6.283185307179586/2π = 1 inches and Diameter = 2r = {2*radius} inches
The Area of the circle = 2Π x Radius = Π x 12 = 3.14 inches

You are given a circle with a circumference 87.96 cm. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 87.96459430051421/2π = 14 cm and Diameter = 2r = {2*radius} cm
The Area of the circle = 2Π x Radius = Π x 142 = 615.75 cm

You are given a circle with a circumference 106.81 m. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 106.81415022205297/2π = 17 m and Diameter = 2r = {2*radius} m
The Area of the circle = 2Π x Radius = Π x 172 = 907.92 m

You are given a circle with a circumference 25.13 units. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 25.132741228718345/2π = 4 units and Diameter = 2r = {2*radius} units
The Area of the circle = 2Π x Radius = Π x 42 = 50.27 units

You are given a circle with a circumference 6.28 inches. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 6.283185307179586/2π = 1 inches and Diameter = 2r = {2*radius} inches
The Area of the circle = 2Π x Radius = Π x 12 = 3.14 inches

You are given a circle with a circumference 75.4 cm. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 75.39822368615503/2π = 12 cm and Diameter = 2r = {2*radius} cm
The Area of the circle = 2Π x Radius = Π x 122 = 452.39 cm
Area of the circle = Π x Radius2 = Π x 112 = 380.13 square inches
Perimeter of the circle = 2Π x Radius = 2Π x 11 = 69.12 square inches

A circle has radius 1 cm. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 12 = 3.14 square cm
Perimeter of the circle = 2Π x Radius = 2Π x 1 = 6.28 square cm

A circle has radius 13 m. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 132 = 530.93 square m
Perimeter of the circle = 2Π x Radius = 2Π x 13 = 81.68 square m

A circle has radius 8 units. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 82 = 201.06 square units
Perimeter of the circle = 2Π x Radius = 2Π x 8 = 50.27 square units

A circle has radius 8 inches. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 82 = 201.06 square inches
Perimeter of the circle = 2Π x Radius = 2Π x 8 = 50.27 square inches

A circle has radius 6 cm. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 62 = 113.1 square cm
Perimeter of the circle = 2Π x Radius = 2Π x 6 = 37.7 square cm

A circle has radius 13 m. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 132 = 530.93 square m
Perimeter of the circle = 2Π x Radius = 2Π x 13 = 81.68 square m

A circle has radius 20 units. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 202 = 1256.64 square units
Perimeter of the circle = 2Π x Radius = 2Π x 20 = 125.66 square units

A circle has radius 16 inches. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 162 = 804.25 square inches
Perimeter of the circle = 2Π x Radius = 2Π x 16 = 100.53 square inches

A circle has radius 6 cm. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 62 = 113.1 square cm
Perimeter of the circle = 2Π x Radius = 2Π x 6 = 37.7 square cm

A circle has radius 4 m. What is the area and the perimeter (circumference) of the circle?

Area of the circle = Π x Radius2 = Π x 42 = 50.27 square m
Perimeter of the circle = 2Π x Radius = 2Π x 4 = 25.13 square m

A circle has area 1017.88 square inches. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 18 inches and Diameter = 2r = {2*radius} inches
The Circumference of the circle = 2Π x Radius = 2Π x 18 = 113.1 inches

A circle has area 615.75 square cm. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 14 cm and Diameter = 2r = {2*radius} cm
The Circumference of the circle = 2Π x Radius = 2Π x 14 = 87.96 cm

A circle has area 3.14 square m. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 1 m and Diameter = 2r = {2*radius} m
The Circumference of the circle = 2Π x Radius = 2Π x 1 = 6.28 m

A circle has area 78.54 square units. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 5 units and Diameter = 2r = {2*radius} units
The Circumference of the circle = 2Π x Radius = 2Π x 5 = 31.42 units

A circle has area 804.25 square inches. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 16 inches and Diameter = 2r = {2*radius} inches
The Circumference of the circle = 2Π x Radius = 2Π x 16 = 100.53 inches

A circle has area 1385.44 square cm. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 21 cm and Diameter = 2r = {2*radius} cm
The Circumference of the circle = 2Π x Radius = 2Π x 21 = 131.95 cm

A circle has area 530.93 square m. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 13 m and Diameter = 2r = {2*radius} m
The Circumference of the circle = 2Π x Radius = 2Π x 13 = 81.68 m

A circle has area 3.14 square units. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 1 units and Diameter = 2r = {2*radius} units
The Circumference of the circle = 2Π x Radius = 2Π x 1 = 6.28 units

A circle has area 1256.64 square inches. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 20 inches and Diameter = 2r = {2*radius} inches
The Circumference of the circle = 2Π x Radius = 2Π x 20 = 125.66 inches

A circle has area 1017.88 square cm. What is the radius of the circle? What is the diameter? What is the circumference?

Area = (π x Radius2) =>
Radius = (A/π)1/2 = 18 cm and Diameter = 2r = {2*radius} cm
The Circumference of the circle = 2Π x Radius = 2Π x 18 = 113.1 cm

You are given a circle with a circumference 37.7 inches. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 37.69911184307752/2π = 6 inches and Diameter = 2r = {2*radius} inches
The Area of the circle = 2Π x Radius = Π x 62 = 113.1 inches

You are given a circle with a circumference 169.65 cm. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 169.64600329384882/2π = 27 cm and Diameter = 2r = {2*radius} cm
The Area of the circle = 2Π x Radius = Π x 272 = 2290.22 cm

You are given a circle with a circumference 100.53 m. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 100.53096491487338/2π = 16 m and Diameter = 2r = {2*radius} m
The Area of the circle = 2Π x Radius = Π x 162 = 804.25 m

You are given a circle with a circumference 150.8 units. What is the radius of the circle? What is the diameter? What is the area of the circle?

Radius of the circle = (Circumference/2π) =>
Radius = 150.79644737231007/2π = 24 units and Diameter = 2r = {2*radius} units
The Area of the circle = 2Π x Radius = Π x 242 = 1809.56 units