Scale Drawings Models Scale Drawings Models l Distances

Scale Drawings & Models

Scale Drawings & Models l Distances on a scale drawing or model are proportional to real-life distances. The scale is determined by the ratio of a length on a drawing or model to its corresponding actual length.

Examples l The local school district has made a scale model of a campus of Engels Middle School including a proposed new building. The scale of the model is 1 inch = 3 feet. New Building Gym Parking Academic Building

Example Continued… l An existing gym is 8 inches tall in the model. How tall is the actual gymnasium? Set up a proportion… New Building Gym Parking 1 3 = 8 X Academic Building 1(x) = 3(8) X = 24 feet tall

l To find the scale factor for scale drawings and models, write the ratio given by the scale in simplest form. 1 Write the ratio of 1 inch to 1 feet in 3 simplest form. 1 inch 1 1 Feet 3 = 1 in. 16 in. Conversion: 1 foot = 12 inches

Example… 3 l On a map, two cities are 5 4 inches apart. The scale of the map is 0. 5 inch = 3 miles. What is the actual distance between the towns? Set up a proportion. 0. 5 inch 3 miles = 5 3 4 3 0. 5 X = 3(5 4 ) inch X miles 0. 5 X = 17. 25 X = 34. 5 miles

Example l Marta is making a scale drawing of her apartment for a school project. The apartment is 28 feet wide. On her drawing, the apartment is 7 inches wide. What is the scale of Marta’s drawing? Set up a proportion. 28 feet 7 inches = 4 feet 1 inch = 4 feet 28 feet