Question

solve the missing element for each problem. Use 3.14 for 兀.Question 2.

Answer 1

2) Recall that in a circle:

$\begin{gathered} \text{radius}=\frac{\text{diameter}}{2}, \\ \text{Circumference}=\pi\cdot\text{diameter,} \\ \text{Area}=\pi\cdot\text{radius}^2\text{.} \end{gathered}$

If a circle has a diameter of 28 mm, then its radius is:

$\text{radius}=\frac{28\operatorname{mm}}{2}=14\operatorname{mm}\text{.}$

And its circumference is:

$\begin{gathered} \text{Circumference}=\pi\cdot28\operatorname{mm}\approx3.14\cdot28\operatorname{mm} \\ =87.92\operatorname{mm} \end{gathered}$

Finally, the area of the circle is:

$\begin{gathered} \text{Area}=\pi\cdot\text{radius}^2=\pi\cdot(14\operatorname{mm})^2 \\ \approx3.14\cdot196mm^2=615.44mm^2\text{.} \end{gathered}$

Answer:

$\begin{gathered} \text{Radius}=14\operatorname{mm}, \\ \text{Circumference}=87.92\operatorname{mm}\text{.} \\ \text{Area}=615.44mm^2\text{.} \end{gathered}$