To find out how much sugar is needed for 15 cups of flour, you can set up a proportion based on the recipe.
The ratio of sugar to flour is given as 2 cups of sugar for every 5 cups of flour.
You can set up the proportion as follows:
\[ \frac{2 \text{ cups of sugar}}{5 \text{ cups of flour}} = \frac{x \text{ cups of sugar}}{15 \text{ cups of flour}} \]
Now, cross-multiply to solve for \(x\):
\[ 2 \times 15 = 5 \times x \]
This simplifies to:
\[ 30 = 5x \]
Now, divide both sides by 5:
\[ x = \frac{30}{5} = 6 \]
So, you will need 6 cups of sugar for 15 cups of flour.