The front of the scale model of a building is 2.5 ft wide. The scale of the model is 1:35. What is the actual width of the front of the building?

Set up the proportion \(\frac {2.5}{\text{x}} = \frac{1}{35}\)2.5/x = 1/35. To solve for x, multiply both sides of the equation by x to get \(2.5 = \frac{\text{x}}{35}\). Then multiply both sides of the equation by 35 to get \( x = {\rm{2}}.{\rm{5}} \times {\rm{35}} = {\rm{87}}.{\rm{5}}\)