When you switch between fractions and percentages, here are some common mistakes to watch out for:

1. Not knowing how to convert: When you want to change a fraction to a percentage, remember to multiply by $100$. For example, $\frac{1}{4}$ can be turned into $0.25 \times 100$ which equals $25\%$.

2. Forgetting to make it simpler: Sometimes, you can make fractions simpler before changing them. This can make things easier. For example, $\frac{2}{4}$ can be simplified to $\frac{1}{2}$ before you multiply by $100$.

3. Getting the decimal wrong: When changing decimals to percentages, remember to move the decimal point two spaces to the right! For example, $0.75$ becomes $75\%$.

If you avoid these mistakes, you'll be converting between fractions and percentages like a pro!