Solve For P F80618
1. **State the problem:** Given the equation $5p^{-3} = 8 \times 5^{-2}$, find the value of $p$.
2. **Recall the rules:**
- Negative exponents mean reciprocal: $a^{-n} = \frac{1}{a^n}$.
- When multiplying powers with the same base, add exponents: $a^m \times a^n = a^{m+n}$.
3. **Rewrite the equation:**
$$5p^{-3} = 8 \times 5^{-2}$$
4. **Express $p^{-3}$ as $\frac{1}{p^3}$:**
$$5 \times \frac{1}{p^3} = 8 \times 5^{-2}$$
5. **Simplify $5^{-2}$:**
$$5^{-2} = \frac{1}{5^2} = \frac{1}{25}$$
6. **Substitute back:**
$$\frac{5}{p^3} = 8 \times \frac{1}{25} = \frac{8}{25}$$
7. **Cross multiply to solve for $p^3$:**
$$5 \times 25 = 8 \times p^3$$
$$125 = 8p^3$$
8. **Divide both sides by 8:**
$$p^3 = \frac{125}{8}$$
9. **Take cube root of both sides:**
$$p = \sqrt[3]{\frac{125}{8}} = \frac{\sqrt[3]{125}}{\sqrt[3]{8}} = \frac{5}{2}$$
**Final answer:** $p = \frac{5}{2}$
This corresponds to option E.