A 1.5 m tall student casts a shadow 2 m long. At the same moment a tree casts a shadow 12 m long. How tall is the tree?
Answer and explanation
Correct answer: B. 9 m (similar triangles: 1.5/2 = h/12)
- Step 1: The triangles are similar, so height / shadow is constant: . Step 2. m. Answer: 9 m. Why not the others: 16 m inverts the ratio; 10.5 m and 8 m come from adding instead of using proportion.
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