Anonymous
Anonymous asked in Science & MathematicsMathematics · 7 months ago

# Find the radius of a circle with a circumference of 64 pi inches.?

How do you get that so I can jot down for future reference. I know the A= pi r^2 but cant get this one.

Relevance
• 7 months ago

Circumference = 2🥧r (sorry, I can’t do pi on my iPhone and I didn’t want you to confuse it as p*i).

64🥧 = 2🥧r

r = 32

• Como
Lv 7
7 months ago

-

C = 2 π r

2 π r = 64 π

r = 32 ins

• Anonymous
7 months ago

c = 2πr

64π = 2πr

Cancel π

64 = 2r

32 = 1r

r = 32

Source(s): Been there
• alex
Lv 7
7 months ago

circumference C=2πr

• 7 months ago

C = 2 pi r

2 pi r = 64 pi inches

r = 32"

• Anonymous
7 months ago

C = 2 pi R

C = pi D

pi = 3.14

pi = 22/7

Substitute given values into equation

64 = 2 X 3.14 X R

64/ 6.28 = R

10.19 = R

You can also use estimation to get you in the right ballpark

• 7 months ago

d = circ/pi = D 20.38 divided by 2 = r 10.19

• Φ² = Φ+1
Lv 7
7 months agoReport

"d = circ/pi = D 20.38 divided by 2 = r 10.19" — How does 64π / π = 20.38 ?