A recipe calls for $4 \frac{1}{2}$ cups of flour. If you only make half of the recipe, then how many cups of flour do you need?
(A) $2 \frac{1}{2}$
(B) $2 \frac{1}{4}$
(C) 9
(D) 2
(E) $2 \frac{3}{4}$
Solution 1

To make half of the recipe, only half of the $4 \frac{1}{2}$ cups of flour are needed.

Since half of 4 is 2 and half of $\frac{1}{2}$ is $\frac{1}{4}$, then $2 \frac{1}{4}$ cups of flour are needed.

Solution 2

To make half of the recipe, only half of the $4 \frac{1}{2}$ cups of flour are needed.

To determine half of $4 \frac{1}{2}$, we divide $4 \frac{1}{2}$ by 2 , or multiply by $\frac{1}{2}$.

Thus, $4 \frac{1}{2} \times \frac{1}{2}=\frac{9}{2} \times \frac{1}{2}=\frac{9}{4}=2 \frac{1}{4}$ cups of flour are needed to make half of the recipe.