12. \( \frac{5}{9}-\frac{3}{8} \)

To find the difference between \( \frac{5}{9} \) and \( \frac{3}{8} \), we first need to determine a common denominator. The least common multiple (LCM) of 9 and 8 is 72. Next, we convert each fraction: \( \frac{5}{9} \) becomes \( \frac{5 \times 8}{9 \times 8} = \frac{40}{72} \) and \( \frac{3}{8} \) becomes \( \frac{3 \times 9}{8 \times 9} = \frac{27}{72} \). Now we can subtract: \( \frac{40}{72} - \frac{27}{72} = \frac{40 - 27}{72} = \frac{13}{72} \). So, \( \frac{5}{9} - \frac{3}{8} = \frac{13}{72} \). To keep your fraction-solving skills sharp, try converting fractions into decimals to see if they feel more intuitive! It can help visualize the size of the numbers. For example, \( \frac{5}{9} \approx 0.56 \) and \( \frac{3}{8} = 0.375 \), making it clear that \( \frac{5}{9} \) is larger, leading to a positive result when you subtract. Also, a common mistake in subtracting fractions is forgetting to find a common denominator. Always check that you’ve got that right before subtracting! Using LCM is a reliable strategy to ensure accuracy.