How do you find the missing value of a proportions?

To find the missing value in a proportion, you can set up a ratio equation based on the known values. For example, if you have the proportion ( \frac{a}{b} = \frac{c}{x} ), you can cross-multiply to get ( a \cdot x = b \cdot c ). Then, solve for the missing value ( x ) by rearranging the equation to ( x = \frac{b \cdot c}{a} ). This method allows you to find the unknown value using the relationships established by the proportion.