Answer:
Circle Calculator
Area Circunference
Inputs:
Radius:
0.25
or
Diameter
0.5
or
Circumference:
1.571
Unit:
Calculate Area
Result:
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The area of a circle with diameter 0.5 is 0.1963
Formulae:
r = 0.25
d = 0.5
C = 1.57
A = πr2 = π(d
2
)2 A = C2
4π
π = 3.1415
A = area
C = circumference or perimeter
r = radius, d = diameter
Solution Steps:
Area of a circle in terms of radius:
Area = π·r2 = 3.14·0.252 = 0.2 square m(*)
Area of a circle in terms of diameter:
Area = π·(d
2
)2 = 3.14·(0.5
2
)2 = 3.14·(0.25)2 = 0.2 square m(*)
Area of a circle in terms of circumference:
Area = C2
4π
= 1.572
4π
= 2.47
(4·3.14)
= 2.47
12.56
= 0.2 square m(*)
(*) 0.19634954084936 m, exactly or limited to the precision of this calculator (13 decimal places).
Note: for simplicity, the operations above were rounded to 2 decimal places and π was rounded to 3.14.
