7. \( \frac{8}{9}-\frac{2}{4}= \)

To solve \( \frac{8}{9} - \frac{2}{4} \), first simplify \( \frac{2}{4} \) to \( \frac{1}{2} \). Now, you have \( \frac{8}{9} - \frac{1}{2} \). To subtract these fractions, find a common denominator, which is 18 in this case. Convert both fractions: \( \frac{8}{9} = \frac{16}{18} \) and \( \frac{1}{2} = \frac{9}{18} \). Now, subtract: \( \frac{16}{18} - \frac{9}{18} = \frac{7}{18} \). So, the final answer is \( \frac{7}{18} \). Remember, when working with fractions, always look for the simplest forms and a common denominator! It's an easy mistake to overlook simplifications or common denominators, causing unnecessary complexity in your calculations.