## Intermediate Algebra (12th Edition)

$\frac{1}{6^{10}}$
According to the quotient rule for exponents, $\frac{a^{m}}{a^{n}}=a^{m-n}$ (where $a\ne0$). Therefore, $\frac{6^{-3}}{6^{7}}=6^{-3-7}=6^{-10}$. Furthermore, the definition of negative exponents tells us that $a^{-n}=\frac{1}{a^{n}}$. Therefore, $6^{-10}=\frac{1}{6^{10}}$.