exercise: circle area and perimeter problem 4
A circle has an area of 140.2 square meters.
a) calculate the radius of the circle
b) calculate the the diameter of the circle.
c) calculate the perimeter of the circle
answer: circle area and perimeter problem 4
a) answer radius
A = r² * π (π = 3.1415..)
140.2 = r² * π / : π
44.627…. = r² / √
r = 6.68 meters
A: The radius of the circle is 6.68 meters
b) answer diameter
d = 2 * r
d = 2 * 6.68
d = 13.36 meters
A: The diameter of the circle is 13.36 meters.
c) answer perimeter
P = d * π
P = 13.36 * π
P = 41.97 meters
A: The perimeter of the circle is 41.97 meters.