Difficulty: Easy
Correct Answer: 173 m
Explanation:
Introduction / Context:This is a direct tangent application in a right triangle formed by the tower (vertical), the ground (horizontal), and the line of sight.
Given Data / Assumptions:
Concept / Approach:tan θ = opposite / adjacent = h / x ⇒ x = h / tan θ.
Step-by-Step Solution:
tan 30° = 1/√3.x = 100 / (1/√3) = 100√3 ≈ 173 m.Verification / Alternative check:Back check: tan 30° = 100 / 173 ≈ 0.577? No—use exact √3: 100 / (100√3) = 1/√3 ✔ (≈ 0.577 inverse is 1.732 for √3).
Why Other Options Are Wrong:100 m assumes 45°; 200 or 273 m do not satisfy tan 30°; 150 m is an arbitrary round-off.
Common Pitfalls:Confusing sine and tangent; approximating √3 poorly; unit conversion is not needed here.
Final Answer:173 m
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