To find the circumference of a circle when we know its area, we can follow a few steps. First, we start by using the formula for the area of a circle, which is:
A = πr²
Here, A is the area, and r is the radius of the circle. According to the question, the area is 121π square inches. We can set up the equation:
121π = πr²
Next, we can divide both sides of the equation by π (assuming π is not zero, which it is not):
121 = r²
Now, we solve for r by taking the square root of both sides:
r = √121 = 11 inches
Now that we have the radius, we can find the circumference (C) of the circle using the circumference formula:
C = 2πr
Substituting the radius we found:
C = 2π(11) = 22π inches
Therefore, the circumference of the circle is 22π inches.