how do u find the perimeter of a circle?
wats the formula>?
thx
2006-10-20 06:02:15 · 10 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
2 * pi * r
2006-10-20 17:33:17 · answer #1 · answered by Nobody 3 · 0⤊ 0⤋
The distance around a circle is called the circumference. The distance across a circle through the center is called the diameter. Pi is the ratio of the circumference of a circle to the diameter.
For any circle, if you divide the circumference by the diameter, you get a value close to Pi. This relationship is expressed in the following formula:
C over d equals Pi
where C is circumference and d is diameter.
Another way to write this formula is: C equals Pi times d.
nice visual answer here: http://www.mathgoodies.com/lessons/vol2/circumference.html
2006-10-20 13:05:57 · answer #2 · answered by Anonymous · 0⤊ 0⤋
the perimeter of a circle is called the circumference. To work out the circumference you multiply the diameter by pi. Or you can multiply the radius by two, then multiply that answer by pi
2006-10-20 15:58:54 · answer #3 · answered by gremlin_lemon 2 · 0⤊ 0⤋
The perimeter of a circle has a special name 'circumference'.
The formula is Circumference = pi * diameter
2006-10-20 13:06:20 · answer #4 · answered by Puzzling 7 · 0⤊ 0⤋
The "perimeter" of a circle is almost always referred to as the circumference, and it is calculated from pi*diameter or 2*pi*radius, where pi is a constant.
The value of pi to two decimal places is 3.14, but pi is a non-repeating decimal that can be expressed to as many places as you want. Its true decimal expansion is infinite.
2006-10-20 13:03:04 · answer #5 · answered by DavidK93 7 · 1⤊ 0⤋
perimeter of the circle = 2(pi)r where r is the radius of the circle
also
= (pi)d where d is the diameter of the circle
2006-10-21 01:48:31 · answer #6 · answered by grandpa 4 · 0⤊ 0⤋
2 pi r
2006-10-20 13:05:48 · answer #7 · answered by Troy J 3 · 0⤊ 0⤋
pi x radius x 2 = pi x diameter, so what he said
2006-10-20 13:05:32 · answer #8 · answered by big_j_gizzy 4 · 0⤊ 0⤋
pie(usually 3.14 or 22/7) x diameter..
2006-10-20 13:06:29 · answer #9 · answered by Lamer0909 1 · 0⤊ 0⤋
Sunny Beach! Everybody is right!!!!!!!!!!!!!!!!!!
2006-10-20 13:11:25 · answer #10 · answered by bob h 5 · 0⤊ 0⤋