Question

For a given recipe, 10 cups of flour are mixed with 15 cups of sugar. How many cups of flour should be used if 24 cups of sugar are used?

Answer 1

You can start by setting up two equal ratios to form the proportion:

$\begin{gathered} a\colon b=c\colon d \\ 10\text{ cups of flour : 15cups of sugar = x : 24 cups of sugar} \end{gathered}$

Where x is the cups of flour that should be used.

Now, you can rewrite the ratios as fractions:

$\begin{gathered} \frac{a}{b}=\frac{c}{d}\text{ by replacing the values} \\ \frac{10}{15}=\frac{x}{24}\text{ to find x multiply both sides by 24} \\ 24\times\frac{10}{15}=24\times\frac{x}{24}\text{ simplify} \\ \frac{240}{15}=x\text{ reorder terms} \\ x=\frac{240}{15}=16 \end{gathered}$

Thus, if 24 cups of sugar are used, 16 cups of flour should be used