1. **State the problem:** Identify which ratios are equivalent to the ratio $2:20$. 2. **Recall the rule for equivalent ratios:** Two ratios $a:b$ and $c:d$ are equivalent if and only if $\frac{a}{b} = \frac{c}{d}$. 3. **Simplify the given ratio:** $$\frac{2}{20} = \frac{\cancel{2}}{\cancel{20}} = \frac{1}{10}$$ 4. **Check each ratio for equivalence:** - $9:15$: $$\frac{9}{15} = \frac{\cancel{3} \times 3}{\cancel{3} \times 5} = \frac{3}{5} \neq \frac{1}{10}$$ - $5:50$: $$\frac{5}{50} = \frac{\cancel{5}}{\cancel{50}} = \frac{1}{10}$$ Equivalent. - $10:100$: $$\frac{10}{100} = \frac{\cancel{10}}{\cancel{100}} = \frac{1}{10}$$ Equivalent. - $14:4$: $$\frac{14}{4} = \frac{7}{2} \neq \frac{1}{10}$$ 5. **Conclusion:** The ratios equivalent to $2:20$ are $5:50$ and $10:100$. **Final answer:** $5:50$ and $10:100$ are equivalent to $2:20$.