How to find a ratio of exponents

Practice Questions

GRE Quantitative Reasoning › How to find a ratio of exponents

Questions

If and are both rational numbers and $4^{m} = 8^{n}$ , what is $\frac{m}{n}$ ?

Quantitative Comparison

Quantity A: $4^5 * 4^{-3}$

Quantity B: $\frac{4^5}{4^{-3}}$