Answer:
written out in the explanation.
Step-by-step explanation:
Area of a circle = [tex]\pi r^{2}[/tex]
Circumference of a circle = [tex]2\pi r[/tex]
The radius is the center point of a circle to the edge of a circle. The diameter is a line from one edge of a circle to the opposite edge.
So, the radius is simply half of the diameter.
For circle A, the radius is 12. Therefore, the diameter is 24.
The circumference is 2·[tex]\pi[/tex]·12 ≈ 75.39822 inches. rounded, the circumference is 75.4 inches.
The area is [tex]\pi 12^{2}[/tex] ≈ 452.38934. rounded, the area is 452.39.
For B,
you have already solved the diameter and radius correctly, good job :). The steps for finding the circumference are the same as for circle A.
the circumference is 2·[tex]\pi[/tex]·6 ≈ 37.69911. rounded, the circumference is 37.7 inches.
the area is [tex]\pi 6^{2}[/tex] ≈ 113.09734. rounded, the area is 113.1.
For C,
the circumference is 12. We can use the circumference equation to solve for the radius.
12 = [tex]2\pi r^{2}[/tex]
divide both by 2[tex]\pi[/tex]
7.63943726841 = [tex]r^{2}[/tex]
square root of 7.63943726841 = 2.76395319577
radius = 2.76395 inches. rounded, the radius is 2.8 inches.
so, radius ·2 = 5.52790639154.
meaning diameter = 5.52791. rounded, the diameter is 5.5 inches.
the area is [tex]\pi 2.76395^{2}[/tex] ≈23.99994. rounded, the area is 24.
