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A palm tree casts a shadow that is 28 feet long. A 6-foot sign casts a shadow 8 feet long.

How tall is the palm tree

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1 Answer

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Answer: The height of the palm tree is 21 feet.

Explanation:

We can use a ratio to solve this:

Actual height to shadow for both objects. The fraction equivalents must be equal.

6/8 = x/28 . Cross multiply

6(28) = 8x

168 = 8x Divide both sides by 8 (8's "cancel" on the right)

168/8 =8x/8

21 = x . This gives us the tree's height as 21 feet.

Another way to solve this is to use the ratios, but simplify the first fraction

6/8 = 3/4

Then multiply the length of the shadow by 3/4

3/4 × 28 = height

28÷4 = 7 7 × 3 = 21

21 feet= the height of the palm tree.

User Tiago Costa
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