To determine how many cups of milk are needed to make 24 waffles, we can use a proportion based on Mr. Jones' original recipe.
The original recipe uses \(\frac{3}{4}\) cups of milk to make 8 waffles.
First, we can find out how much milk is needed for 1 waffle:
\[ \text{Milk per waffle} = \frac{\frac{3}{4} \text{ cups}}{8 \text{ waffles}} = \frac{3}{32} \text{ cups per waffle} \]
Next, we multiply the amount of milk needed per waffle by 24 to find out how much milk is needed for 24 waffles:
\[ \text{Milk for 24 waffles} = 24 \text{ waffles} \times \frac{3}{32} \text{ cups per waffle} = \frac{72}{32} \text{ cups} \]
Now we simplify \(\frac{72}{32}\):
\[ \frac{72}{32} = \frac{9}{4} = 2.25 \text{ cups} \]
Thus, Mr. Jones should use 2.25 cups of milk to make 24 waffles.