Question

I need help with this

Answer 1

`\bold\color{plum}\tt \: Answer \: \: 1 :`

Diameter = 4 cm

Radius = Diameter/2 = 2 cm

Area of circle :

`= \pi{r}^(2)`

`= 3.14 * 2 * 2`

`= 3.14 * 4`

`= 12.56 \: {cm}^(2)`

Circumference of circle :

`= 2\pi r`

`= 2 * 3.14 * 2`

`= 12.56 \: \: {cm}^(2)`

Therefore,

Diameter = 4 cm

Radius = 2 cm

Area = 12.56 cm²

Circumference = 12.56 cm

`\bold{\color{plum}\tt \: Answer \: \: 2 :}`

Circumference = 15 feet (given)

Radius :

`= 2\pi r`

`= 2 * (22)/(7) * r = 15`

`= (44)/(7) * r = 15`

`= 44r = 15 * 7`

`= 44r = 105`

`= r = (105)/(44)`

`= r = 2.38 \: feet`

Diameter = r×2 = 2.38 × 2 = 4.76 feet

Area :

`= \pi {r}^(2)`

`= 3.14 * 2.38 * 2.38`

`= 17.78 \: {ft}^(2)`

Therefore,

Diameter = 4.76 feet

Radius = 2.38 feet

Area = 17.78 ft²

Circumference = 15 feet

`\color{plum}\tt \: Answer \: \: 3 :`

Diameter = 2 cm (given)

Radius = D/2 = 2/2 = 1 cm

Circumference :

`= 2 \pi r`

`= 2 * 3.14 * 1`

`= 6.28 \: feet`

Area :

`= \pi {r}^(2)`

`= 3.14 * 1 * 1`

`= 3.14 \: {ft}^(2)`

Therefore,

Diameter = 2 cm

Radius = 1 cm

Area = 3.14 ft²

Circumference = 6.28 feet

`\color{plum}\tt \: Answer \: \: 4 :`

Radius = 4.3 mm

Diameter = r×2 = 4.3 × 2 = 8.6 mm

Circumference :

`= 2\pi r`

`= 2 * 3.14 * 4.3`

`= 27 \: mm`

Area :

`= \pi {r}^(2)`

`= 3.14 * 4.3 * 4.3`

`= 3.14 * 18.49`

`= 58.05 \: {mm}^(2)`

Therefore,

Diameter = 8.6 mm

Radius = 4.3 mm

Area = 58.95 mm²

Circumference = 27 mm