Question

find the area of the circle. use 3.14 or \\(\frac{22}{7}\\) for \\(\pi\\).
3.
4.
5.
6.
7.
8.

Explanation:

Step1: Find radius of circle 3

The diameter is 9 mm, so radius $r = \frac{9}{2} = 4.5$ mm.

Step2: Calculate area of circle 3

Use formula $A = \pi r^2$. $A = 3.14 \times (4.5)^2 = 3.14 \times 20.25 = 63.585$ mm².

Step3: Find radius of circle 4

Diameter is 14 cm, so radius $r = \frac{14}{2} = 7$ cm.

Step4: Calculate area of circle 4

Use $\pi = \frac{22}{7}$. $A = \frac{22}{7} \times 7^2 = 22 \times 7 = 154$ cm².

Step5: Find radius of circle 5

Diameter is 10 in, so radius $r = \frac{10}{2} = 5$ in.

Step6: Calculate area of circle 5

$A = 3.14 \times 5^2 = 3.14 \times 25 = 78.5$ in².

Step7: Find radius of circle 6

Diameter is 3 in, so radius $r = \frac{3}{2} = 1.5$ in.

Step8: Calculate area of circle 6

$A = 3.14 \times (1.5)^2 = 3.14 \times 2.25 = 7.065$ in².

Step9: Find radius of circle 7

Diameter is 2 cm, so radius $r = \frac{2}{2} = 1$ cm.

Step10: Calculate area of circle 7

$A = 3.14 \times 1^2 = 3.14$ cm².

Step11: Find radius of circle 8

Diameter is 1.5 ft, so radius $r = \frac{1.5}{2} = 0.75$ ft.

Step12: Calculate area of circle 8

$A = 3.14 \times (0.75)^2 = 3.14 \times 0.5625 = 1.76625$ ft².

Answer:

1. $63.585$ mm²
2. $154$ cm²
3. $78.5$ in²
4. $7.065$ in²
5. $3.14$ cm²
6. $1.76625$ ft²