How do you find the circumference and area of a circle?

Answer 1

-- If you know either the area or the circumference of the circle, you can

calculate the other one.

-- If you don't know either the area or the circumference, then you have to

either measure the circle's diameter, or ask around and try to find someone

who already knows what the length of the diameter is.

-- Once you have the diameter, take 1/2 of it. That's called the circle's "radius".

-- The area of the circle is (pi) x (radius)2

-- The circumference of the circle is (2 pi) x (radius) or (pi) x (diameter).

(Pi) is a number that can never be exactly written down, so the best you can do is

use some number that's close. The closer your number is to (pi), the closer your

answer will be to the truth, but it can never be exactly and perfectly correct.

(Pi) is approximately 3.1415926 .

But the easiest and most practical way to work with it is to use 22/7 for it.

If you do that, then your answers are only about 0.04 percent wrong, and

that's actually pretty darn good.

Answer 2

Circumference is the length around the circle

C = 2 pi (r)

r is radius half of diameter

Area of a circle is the number of square units inside the circle

A = pi (r)^2

r is the radius again

Answer 3

Multiply the length or diameter by pi (approximately 3.14) to find the circumference. For the area of a circle, multiply pi by the radius squared.

A = pi * r2

C= pi * D