Presentation on theme: "EXAMPLE 4 Use a scale drawing Maps"— Presentation transcript:
1 EXAMPLE 4Use a scale drawingMapsThe scale of the map at the right is 1 inch : 26 miles. Find the actual distance from Pocahontas to Algona.SOLUTIONUse a ruler. The distance from Pocahontas to Algona on the map is about 1.25 inches. Let x be the actual distance in miles.
2 The actual distance from Pocahontas to Algona is about 32.5 miles. EXAMPLE 4Use a scale drawing1.25 in.x mi26 mi1 in.=distance on mapactual distance=1.25 (26)xCross Products Propertyx=32.5Simplify.The actual distance from Pocahontas to Algona is about 32.5 miles.
3 EXAMPLE 5Solve a multi-step problemScale ModelYou buy a 3-D scale model of the Reunion Tower in Dallas, TX. The actual building is 560 feet tall. Your model is 10 inches tall, and the diameter of the dome on your scale model is about 2.1 inches.What is the diameter of the actual dome?a.b.About how many times as tall as your model is the actual building?
4 Solve a multi-step problem EXAMPLE 5Solve a multi-step problemSOLUTION10 in.560 ftx ft2.1 in.=a.measurement on modelmeasurement on actual building=117610 xCross Products Propertyx=117.6Solve for x.The diameter of the actual dome is about 118 feet.ANSWER
5 EXAMPLE 5Solve a multi-step problemb.To simplify a ratio with unlike units, multiply by a conversion factor.560 ft10 in.1 ft12 in.560 ft10 in.==672The actual building is 672 times as tall as the model.ANSWER
6 GUIDED PRACTICEfor Examples 4 and 54. Two cities are 96 miles from each other. The cities are 4 inches apart on a map. Find the scale of the map.ANSWER1 in : 24 mi5. What If ? Your friend has a model of the Reunion Tower that is 14 inches tall. What is the diameter of the dome on your friend’s model?ANSWERAbout 2.95 in.