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Using Proportional Relationships. Geometry CP2 (Holt 7-5) K. Santos. Example 1. On a Wisconsin road map, Kristin measured a distance of 11 in from Madison to Wausau. The scale on this map is 1 inch: 16 miles. What is the actual distance between Madison and Wausau to the nearest mile?
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Using Proportional Relationships Geometry CP2(Holt 7-5) K. Santos
Example 1 On a Wisconsin road map, Kristin measured a distance of 11 in from Madison to Wausau. The scale on this map is 1 inch: 16 miles. What is the actual distance between Madison and Wausau to the nearest mile? = x = 16(11) x = 176 miles
Example 2 Lady Liberty holds a tablet in her left hand. The tablet is 7.2 m long and 4.1 m wide. If you made a scale drawing using the scale 1cm: 0.75m, what would be the dimensions to the nearest tenth? = = .75x = 7.2.75y = 4.1 9.6 cm 5.5 cm
Proportional Perimeters and Areas Theorem (7-5-1) If the similarity ratio of two similar figures is , then The ratio of the perimeters is The ratio of the areas is or
Example 1 In the triangles below, find the similarity ratio, the perimeter ratio and the area ratio. 10 8 4 5 3 6 Similarity ratio: = =all reduce to Perimeter ratio: Area Perimeter: =
Example 2 Given that find the perimeter and area of has perimeter = 36 cm and area = 60. M R 9 cm 12 cm Q S L N Perimeter: = 12P = 324 so Perimeter = 27 cm Area: = = 144A = 4860 so Area=33.75