Answer:
The flagpole is 12.5 ft tall.
Explanation:
The ratio of object height to shadow length is ...
(teen height) : (teen shadow) = (5 ft) : (6 ft) = 5 : 6
so the height of an object is 5/6 the length of its shadow. Then the height of the flagpole is ...
(5/6) · (15 ft) = 12.5 ft
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A suitable scale drawing can show you the answer.