A 1.2 metre tall boy stands vertically at 5 pm when the sun’s altitude is 30°. What is the length of his shadow, rounded to two decimal places?
Answer
2.08 metres
The correct answer is 2.08 metres — Round to two decimal places: metres.
Step-by-step solution
- Draw a right‑angled triangle with the boy’s height as the opposite side and the shadow as the adjacent side.
- Recognise that the angle of elevation of the sun is 30°, which is also the angle of the triangle.
- Use the relation . So .
- Calculate .
- Compute metres.
- Round to two decimal places: metres.
Common mistake: Using wrong trigonometric ratio or wrong angle
Concept tested: Shadow length using trigonometry
Published · How this solution was prepared and checked
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