How do you figure permiter of a circle?

Answer 1

The perimeter of a circle is known as the 'Circumference'.!!

The Algebraic Equation for circumference of a circle is ; -

C = 2 pi r or C = pi d

Were

C = circumference

pi = 3.14.... ~3.14 ( The circular constant)

r = radius (distance from edge to the centre point)

d = 2 r = diameter ( the distance in a straight line from one side to the other through the centre point).

E.g.

If we have a radius (r) of 20 units, then 'd' = 2(20) = 40

Hence

C = 3.14 X 40 = 125.6 units.

or

C = 2 x 3.14 x 20 = 125.6 units.

NB for area of a circle the equation is

A = pi r^(2)

In words, 'Area equals ;pi; multiplied to the radius squared. and the answer is in units squared. (units^(2)).

NNB 'pi' note the spelling, is an irrational number, so when given values of 3.14, 3.1416, 3.141592, 22/7 these are only approximations, but are useful for learning.

Answer 2

The perimeter of a circle is its circumference and it found by 2*pi*radius or pi*diameter