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A telephone pole that is 40 feet tall casts a shadow that is 26 feet long.
Find the height of a mailbox that casts a 1.2 foot shadow.
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Because the Sun is VERY FAR from the Earth, you may think that the sun light goes to the Earth in parallel rays.
It makes the right angled triangles similar (the triangle "the pole and its shadow" on one side, and
the triangle "mailbox and its shadow", on the other side).
From the triangles similarity, you have this proportion
= .
From the proportion find x = = 1.85 ft as the height of the mailbox. Answer
Solved.