To solve the problem of finding the circumference and area of a circle with a diameter of 7 cm, we need to follow several steps.
### Step 1: Given Information
- The diameter of the circle (D) is 7 cm.
- The value for π (pi) is 3.14.
### Step 2: Calculate the Radius
The radius (R) of a circle is half of its diameter. We can find the radius using the following formula:
[tex]\[ R = \frac{D}{2} \][/tex]
For this specific problem:
[tex]\[ R = \frac{7 \text{ cm}}{2} = 3.5 \text{ cm} \][/tex]
### Step 3: Calculate the Circumference
The formula to calculate the circumference (C) of a circle is:
[tex]\[ C = 2 \pi R \][/tex]
By substituting the given values:
[tex]\[ C = 2 \times 3.14 \times 3.5 \text{ cm} \][/tex]
Performing the multiplication:
[tex]\[ C = 21.98 \text{ cm} \][/tex]
### Step 4: Calculate the Area
The formula to calculate the area (A) of a circle is:
[tex]\[ A = \pi R^2 \][/tex]
By substituting the given values:
[tex]\[ A = 3.14 \times (3.5 \text{ cm})^2 \][/tex]
Performing the multiplication:
[tex]\[ A = 3.14 \times 12.25 \text{ cm}^2 \][/tex]
[tex]\[ A = 38.465 \text{ cm}^2 \][/tex]
### Summary of Results
- Circumference: The circumference of the circle is 21.98 cm.
- Area: The area of the circle is 38.465 cm².
Therefore, the final answers are:
- Circumference: 21.98 cm
- Area: 38.465 cm²
