what is the area of a circle if the perimeter is 6.81m?

Answer 1

3.69

Answer 2

Circumference = 6.81m

Diameter = 6.81 / Pi = 2.1677m

Radius = Diameter / 2 = 1.0838m

Area = Pi x Radius^2 = Pi x 1.0838^2 = 3.69sqm

There is also a direct formula A = C^2 / (4Pi)

Answer 3

If the circumference (or perimeter) is c, the radius is r, and the area is a, then:
c = 2pi*r ..............(1)
a = pi*r^2 ............(2)
Dividing (1) by 2pi:
r = c / 2pi
Substituting this value in (2):
a = pi (c / 2pi)^2
= c^2 / (4pi).

Substituting the numbers given for your circle:
a = 6.81^2 / (4 pi)
= 11.594 / pi,
and using pi = 3.142 this gives:
a = 11.594 / 3.142
= 3.6900 m^2.

Answer 4

The perimeter is the same as the circumference.

p = pi * d = 2 * pi * r

6.81 = 2 * pi * r
r = 6.81 / (2 * pi) = 1.0838451624558072365860984285668

Area = pi * r² = pi * (1.0838451624558072365860984285668 )² = 3.69049277816202364057566514927

Answer 5

The circumference of a circle is equal to its perimeter

C = P

Area of circle = pi times radius squared or
A = pi x r^2

Circumference = pi times diameter
Assume pi = 3.14
6.81 = 3.14 x d
d = 6.81 / 3.14
d = 2.1688

Radius = diameter divided by 2
r = 2.1688/2
r = 1.0844

Area of circle = pi x r^2
A = 3.14 x 1.0844^2
A = 3.14 x 1.1759
A = 3.6923 sq.m ===> area of circle

Answer 6

divide by pi, get d then (1/2d) ^2 pi= area.can also be figured as d^2/4 pi again dpi =circumfrence. d=diameter d^2/4 = r^2 thus you can figure area using either the diameter or radius. when using diameter square it and divide by four to get the equivelant of radius squared.
now you do the math. i've given you the methods.

Answer 7

P = 2πr
2πr = 6.81
r = 6.81 / 2π
r = 1.08
A = πr²
A = π x (1.08)²
A = 3.69 m² ( to 1 dec.place)

Answer 8

π x d = c (circumference)
3.142 x d = 6.81
d = 6.81 ÷ 3.142 = 2.17m
r = 1.084m. Area = π r² = 3.142 x 1.084 x 1.084
Area = 3.69m² (3.7m²)