Answer:
Step-by-step explanation:
1. R = 37.54 : 2 : 3.14 = 5.977707.... (round to 6)
2. We find the radius first : 20/2 = 10 inches
A = 10.10.3.14 = 314 = 100pi
3.
Radius = 24 : 2 = 12cm
Circumference = approx. 75.4cm
Area = 452.16cm2
Answer:
1. r = 5.98 ft (2 dp)
2. area = 100[tex]\pi[/tex] in²
3. radius = 12 cm
circumference = 24[tex]\pi[/tex] cm ≈ 75.398 cm (3 dp)
area = 144[tex]\pi[/tex] cm² ≈ 452.389 cm² (3 dp)
Step-by-step explanation:
1. circumference of a circle = [tex]2\pi r[/tex] (where r is the radius)
Given:
⇒ 37.54 = 2 x 3.14 x r
⇒ 37.54 = 6.28 r
⇒ r = 37.54 ÷ 6.28
⇒ r = 5.98 ft (2 dp)
2. area of a circle = [tex]\pi r^2[/tex] (where r is the radius)
radius = [tex]\dfrac12d[/tex] (where d is the diameter)
Given:
⇒ area = [tex]\pi[/tex] x 10²
⇒ area = 100[tex]\pi[/tex] in²
3. radius = [tex]\dfrac12d[/tex] (where d is the diameter)
circumference of a circle = [tex]2\pi r[/tex] (where r is the radius)
area of a circle = [tex]\pi r^2[/tex] (where r is the radius)
Given:
⇒ radius = 1/2 x 24 = 12 cm
⇒ circumference = 2 x [tex]\pi[/tex] x 12 = 24[tex]\pi[/tex] cm
⇒ area = [tex]\pi[/tex] x 12² = 144[tex]\pi[/tex] cm²
