Re: The circumference of circle C1 is 12 and the circumference of circle
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02 Aug 2025, 23:05
We are given:
- Circumference of circle $\(\mathrm{C} 1=12 \pi\)$
- Circumference of circle $\(\mathrm{C} 2=48 \pi\)$
The formula for circumference is:
$$
\(C=2 \pi r\)
$$
where $r$ is the radius.
From the circumferences, we can find the radii:
For C1:
$$
\(12 \pi=2 \pi r_1 \Longrightarrow r_1=\frac{12 \pi}{2 \pi}=6\)
$$
For C2:
$$
\(48 \pi=2 \pi r_2 \Longrightarrow r_2=\frac{48 \pi}{2 \pi}=24\)
$$
Next, the area $A$ of a circle is:
$$
\(A=\pi r^2\)
$$
So,
$$
\(\begin{gathered}
A_1=\pi(6)^2=36 \pi \\
A_2=\pi(24)^2=576 \pi
\end{gathered}\)
$$
The ratio of the areas $\(\frac{A_2}{A_1}\)$ is:
$$
\(\frac{576 \pi}{36 \pi}=\frac{576}{36}=16\)
$$
Thus, the ratio of the area of $C_2$ to $C_1$ is 16 to 1 .
Answer: (e) 16 to 1.