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Question
A water tank casts a shadow 21 m long. A tree of height 9.5 m casts a shadow 8 m long at the same time. The lengths of the shadows are directly proportional to their heights. Find the height of the tank.
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Solution
The height of the tree = 9.5 m
The shadow of the tree = 8 m
According to the given condition in the question, the lengths of the shadows are in direct proportion.
∴ `8/9.5 = 21/x`
⇒ `x = (21 xx 9.5)/8 = 199.5/8` = 24.9375 ≈ 24.9 m
Hence, height of the water tank is 24.9 m.
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