Difficulty: Easy
Correct Answer: 1.8 m
Explanation:
Introduction / Context:
When two vertical objects cast shadows at the same time, similar triangles apply: height/shadow is constant. We can scale the man’s shadow by the known ratio from the pole to find the man’s height.
Given Data / Assumptions:
Concept / Approach:
Use height/shadow = constant for both objects (similar right triangles). Thus hman / 2.4 = 6 / 8.
Step-by-Step Solution:
hman = 2.4 × (6/8) = 2.4 × 0.75 = 1.8 m
Verification / Alternative check:
Both give the same tangent ratio: 6/8 = 1.8/2.4 = 0.75, confirming the similarity scaling is correct.
Why Other Options Are Wrong:
Values 1.4, 1.6, 2.0, or 1.5 m do not preserve the same height-to-shadow ratio with a 2.4 m shadow.
Common Pitfalls:
Inverting the ratio (8/6 instead of 6/8); mixing units (they are already in meters).
Final Answer:
1.8 m
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