1. **State the problem:** We are given the formula relating surface area $A$ and volume $V$ of a cube: $$A = 6V^{\frac{2}{3}}$$ and the surface area $A = 486$ square inches. We need to find the volume $V$ in cubic inches.
2. **Write down the formula:** $$A = 6V^{\frac{2}{3}}$$
3. **Substitute the known value:** $$486 = 6V^{\frac{2}{3}}$$
4. **Isolate $V^{\frac{2}{3}}$ by dividing both sides by 6:**
$$\frac{486}{6} = \cancel{6}V^{\frac{2}{3}} \div \cancel{6}$$
$$81 = V^{\frac{2}{3}}$$
5. **To solve for $V$, raise both sides to the power of $\frac{3}{2}$ (the reciprocal of $\frac{2}{3}$):**
$$\left(81\right)^{\frac{3}{2}} = \left(V^{\frac{2}{3}}\right)^{\frac{3}{2}}$$
$$\left(81\right)^{\frac{3}{2}} = V$$
6. **Calculate $\left(81\right)^{\frac{3}{2}}$:**
First, $81 = 9^2$, so
$$\left(9^2\right)^{\frac{3}{2}} = 9^{2 \times \frac{3}{2}} = 9^3 = 729$$
7. **Final answer:**
$$V = 729$$ cubic inches.
**Explanation:** We used the given formula to express volume in terms of surface area, isolated the volume term, and then used exponent rules to solve for $V$. The volume of the cube is 729 cubic inches.
Cube Volume 2B232F
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