## Prealgebra (7th Edition)

Express the given information as a ratio. $\frac{x}{80}=\frac{13}{2}$$\Rightarrowuse cross products to solve for x 2x=13\times80$$\Rightarrow$multiply $2x=1040$$\Rightarrowmultiplication property of equality 2x\div2=1040\div2$$\Rightarrow$divide $x=520$