18. \( \frac{4}{8} \times \frac{3}{4}= \)

To solve \( \frac{4}{8} \times \frac{3}{4} \), we multiply the numerators together and the denominators together. This gives us \( \frac{4 \times 3}{8 \times 4} = \frac{12}{32} \). Now, we can simplify \( \frac{12}{32} \) by dividing both the numerator and denominator by their greatest common divisor, which is 4. This results in \( \frac{3}{8} \). So, \( \frac{4}{8} \times \frac{3}{4} = \frac{3}{8} \). You might find it fun to know that fractions have been used since ancient times, dating back to the Egyptians around 3000 BC! They had a unique way of writing fractions, using a system based on unit fractions, which means they only expressed fractions as sums of fractions with 1 in the numerator. Isn’t it fascinating how math has evolved? When working with fractions, a common mistake is forgetting to simplify at the end! Always remember, after multiplying or adding fractions, check if you can break them down into simpler numbers. Simplifying can make your answers clearer and cleaner, so keep that in mind the next time you're crunching numbers!