Question

Find perimeter of the semicircular region​

Answer 1

Formula to find the perimeter of a semicircular region:

if radius given:
`P=2r` +
`\pi r` {r = radius}

if diameter given:
`P=d+\pi r` {d = diameter}

Take
`\pi` as 3.14

Q4.

Diameter = 28 yd

Radius = 28/2 = 14 yd

`P=28+\pi (14)`

`P=28+(3.14)(14)`

`P=28+14.96`

`P=42.96` yd

Q5.

Radius = 7.5 ft

Diameter = 7.5 × 2 = 15 ft

`P=2(7.5)+\pi (7.5)`

`P=2(7.5)+(3.14)(7.5)`

`P=15+23.55`

`P=38.55` ft

Q6.

Diameter = 11 cm

Radius = 11/2 = 5.5 cm

`P=11+\pi (5.5)`

`P=11+(3.14)(5.5)`

`P=11+17.27`

`P=17.27` cm

I hope this helps...

Have a great day ahead :)

Answer 2

4. 87.96 yd

5. 47.12 ft

6. 34.56 cm

Explanation:

4. diameter(d) = 28 yd,

perimeter = πd = 87.96 yd (rounded to 2 dp)

5. radius(r) = 7.5 ft

perimeter = 2πr = 47.12 ft (rounded to 2 dp)

6. diameter (d) = 11 cm

perimeter = πd = 34.56 cm

Answered by GAUTHMATH