Question

Suppose that the radius of a circle is 9.5 cm.
Question 1
To the nearest tenth, what is the area of the circle? (Use 3.14 for
.)
Responses
A 29.8
29.8 cm 2
B 59.7
59.7 cm 2
C 173.5
173.5 cm 2
D 283.4
283.4 cm 2
Question 2
To the nearest tenth, what is the circumference of the circle? (Use 3.14 for
.)
Responses
A 29.8 cm29.8 cm
B 59.7 cm59.7 cm
C 151.2 cm151.2 cm
D 167.8 cm

Answer 1

To answer your questions, we'll use the formulas for the area and circumference of a circle.

1. **Area of a Circle:**
\[
\text{Area} = \pi r^2
\]

Given:
- Radius \( r = 9.5 \, \text{cm} \)
- Using \( \pi \approx 3.14 \)

\[
\text{Area} = 3.14 \times (9.5)^2
\]
\[
= 3.14 \times 90.25 \quad (\text{since } 9.5^2 = 90.25)
\]
\[
= 283.3 \, \text{cm}^2
\]

Rounding to the nearest tenth, the area is **283.4 cm²**.
**So the answer for Question 1 is D: 283.4 cm².**

2. **Circumference of a Circle:**
\[
\text{Circumference} = 2\pi r
\]

Using the same values:
\[
\text{Circumference} = 2 \times 3.14 \times 9.5
\]
\[
= 6.28 \times 9.5
\]
\[
= 59.66 \, \text{cm}
\]

Rounding to the nearest tenth, the circumference is **59.7 cm**.
**So the answer for Question 2 is B: 59.7 cm.**