Question

Find the length of the​ radius, the​ circumference, and the area of the circle. Use 3.14 for pi.
.
.
.
Question content area top right
Part 1
         
28.2 cm

Question content area bottom
Part 1
The radius is
  
14.1
cm.
​(Simplify your answer. Type an integer or a​ decimal.)
Part 2
The circumference is approximately
  
enter your response here
▼
cm cubed .
cm squared .
cm.
​(Simplify your answer. Type an integer or a decimal. Round to the nearest hundredth as​ needed.)

Answer 1

To find the radius, circumference, and area of a circle, we can use the following formulas:

1. **Radius (r)**: The radius is half of the diameter. Given the diameter is 28.2 cm:
\[
r = \frac{28.2}{2} = 14.1 \text{ cm}
\]

2. **Circumference (C)**: The circumference is calculated using the formula:
\[
C = 2\pi r
\]
Substituting the values with \(\pi\) as 3.14:
\[
C = 2 \times 3.14 \times 14.1
\]
\[
C \approx 2 \times 3.14 \times 14.1 = 88.838 \text{ cm}
\]
Rounded to the nearest hundredth:
\[
C \approx 88.84 \text{ cm}
\]

3. **Area (A)**: The area is calculated using the formula:
\[
A = \pi r^2
\]
Substituting the values:
\[
A = 3.14 \times (14.1)^2
\]
\[
A \approx 3.14 \times 198.81 \approx 624.9994 \text{ cm}^2
\]
Rounded to the nearest hundredth:
\[
A \approx 625.00 \text{ cm}^2
\]

Putting it all together:
- The radius is **14.1 cm**.
- The circumference is approximately **88.84 cm**.
- The area is approximately **625.00 cm²**.