1. **State the problem:** We have a right circular cylinder with radius $r$ and height $h$. A second cylinder has volume 392 times the volume of the first. We want to find possible radius $R$ and height $H$ of the second cylinder in terms of $r$ and $h$.
2. **Formula for volume of a cylinder:**
$$V = \pi r^2 h$$
3. **Volume of first cylinder:**
$$V_1 = \pi r^2 h$$
4. **Volume of second cylinder:**
$$V_2 = 392 V_1 = 392 \pi r^2 h$$
5. **Express $V_2$ in terms of $R$ and $H$:**
$$V_2 = \pi R^2 H$$
6. **Set volumes equal:**
$$\pi R^2 H = 392 \pi r^2 h$$
7. **Cancel $\pi$ on both sides:**
$$\cancel{\pi} R^2 H = 392 \cancel{\pi} r^2 h$$
8. **Divide both sides by $r^2 h$:**
$$\frac{R^2 H}{r^2 h} = 392$$
9. **Rewrite as:**
$$\left(\frac{R}{r}\right)^2 \cdot \frac{H}{h} = 392$$
10. **Check each option:**
- (a) $R=8r$, $H=7h$:
$$8^2 \times 7 = 64 \times 7 = 448 \neq 392$$
- (b) $R=8r$, $H=49h$:
$$8^2 \times 49 = 64 \times 49 = 3136 \neq 392$$
- (c) $R=7r$, $H=8h$:
$$7^2 \times 8 = 49 \times 8 = 392$$ (Correct)
- (d) $R=49r$, $H=8h$:
$$49^2 \times 8 = 2401 \times 8 = 19208 \neq 392$$
**Final answer:** Option (c) $R=7r$ and $H=8h$ satisfies the volume condition.
Cylinder Volume 8Bc0Ba
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