A recipe for cornbread calls for 2 cups of flour for every

4
1

cup of water. Using the same recipe, how much water will you need for 9 cups of flour?
Start by setting up a table that could be used to find how many cups of water you will need for 9 cups of flour.
Cups of Flour Cups of Water

2

4
1



9

?
Excellent!
How many cups of water will you need for 9 cups of flour? Fill in that information in the table. Solve on paper. Then, enter your answer on Zearn.
Cups of Flour Cups of Water
2
4
1


9

as a fraction

1 answer

To find out how many cups of water you need for 9 cups of flour, you can set up a proportion based on the initial recipe.

The original ratio from the recipe is:

  • 2 cups of flour requires 4.5 cups of water (since 4 1/2 cups can be expressed as 4.5).

Let's set this up in a table format:

| Cups of Flour | Cups of Water | |---------------|---------------| | 2 | 4.5 | | 4 | 9.0 | | 9 | ? |

To find the amount of water needed for 9 cups of flour, we can set up a proportion based on the known quantities:

\[ \frac{2 \text{ cups flour}}{4.5 \text{ cups water}} = \frac{9 \text{ cups flour}}{x \text{ cups water}} \]

Cross-multiplying to solve for \( x \):

\[ 2x = 9 \cdot 4.5 \]

Calculating \( 9 \cdot 4.5 \):

\[ 9 \cdot 4.5 = 40.5 \]

So we have:

\[ 2x = 40.5 \]

Now, divide both sides by 2:

\[ x = \frac{40.5}{2} = 20.25 \]

Therefore, for 9 cups of flour, you will need 20.25 cups of water.

Now, filling in the table:

| Cups of Flour | Cups of Water | |---------------|---------------| | 2 | 4.5 | | 4 | 9.0 | | 9 | 20.25 |

To enter the answer as a fraction, you can express 20.25 as \( \frac{81}{4} \) (since 20.25 = 20 + 0.25 = 20 + \frac{1}{4} = \frac{80}{4} + \frac{1}{4} = \frac{81}{4}).

Thus, the answer for the amount of water needed for 9 cups of flour is \( \frac{81}{4} \) cups of water.