Geometry: An Interactive Journey to Mastery

Lesson 24: Introduction to Scale

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Find the ratios area I + area IIarea I and area IIarea I for )LJXUH.

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DQGDVKDUHGDQJOH௘ͽZLWKVFDOHIDFWRUk 115 or^115 , depending on one’s perspective. Thus,

area I area IIarea I^ k^212125.

Algebra then gives the following.

121 area I 25 area I area II

121 area I 25 area I 25 area II

96 area I 25 area II.

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area IIarea I 9625.

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A model ship is built in the scale of 1:100.

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real ship?

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real ship?

F௘ͽ ,IWKHOHQJWKRIDPDVWRQWKHUHDOVKLSLVIHHWZKDWLVWKHOHQJWKRIWKHPDVWRQWKHPRGHO"

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on the model?

6

(^5) I II
Figure 24.2