## Prealgebra (7th Edition)

Write a proportion using the given scale. Cross multiply to solve for x. $\frac{\frac{1}{4}in}{10ft}=\frac{5in}{x\ ft}$ $\frac{1}{4}\times x=5\times 10$ $\frac{1}{4}x=50$ $\frac{1}{4}x\times4=50\times4$ $x=200$ $\frac{\frac{1}{4}in}{10ft}=\frac{7\frac{1}{2}in}{x\ ft}$ $\frac{1}{4}\times x=7\frac{1}{2}\times 10$ $\frac{1}{4}\times x=\frac{15}{2}\times 10$ $\frac{1}{4}\times x=\frac{150}{2}$ $\frac{1}{4}x=75$ $\frac{1}{4}x\times4=75\times4$ $x=300$ $\frac{\frac{1}{4}in}{10ft}=\frac{10\frac{5}{8}in}{x\ ft}$ $\frac{1}{4}\times x=10\frac{5}{8}\times 10$ $\frac{1}{4}\times x=\frac{85}{8}\times 10$ $\frac{1}{4}\times x=\frac{850}{8}$ $\frac{1}{4}x=\frac{850}{/\!\!4\times2}\times/\!\!\!4$ $\frac{1}{4}x\times4=\frac{850}{2}$ $x=425$