Find the length of a circle whose radius is 4 cm. What is the area of the circle bounded by this circle?

From the condition, we know that the circle is given to us by its radius and it is equal to R = 4 cm.

Let’s start by calculating the circumference. Let’s remember what formula is used for this:

C = 2nR.

In the formula, R is the radius of the circle, and the number n = 3.14.

We just have to substitute values and perform calculations:

C = 2 * 3.14 * 4 = 8 * 3.14 = 25.12 cm.

Now we will remember and apply the formula for finding the area of a circle bounded by this circle:

S = nR ^ 2;

Substitute the values and calculate:

S = 3.14 * 4 ^ 2 = 3.14 * 16 = 50.24 cm ^ 2.