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TIER 7 — CHALLENGE 003 — The Mountain Shadow Geometry - Printable Version

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TIER 7 — CHALLENGE 003 — The Mountain Shadow Geometry - Leejohnston - 11-14-2025

[border]TIER 7 — Advanced Reasoning[/border]

Tier 7 — Challenge 003 — The Mountain Shadow Geometry

At sunrise, a tall mountain casts a shadow across a valley.

• Mountain height: **2,480 m** 
• Angle of sunlight above the horizon: **7.5°** 
• The mountain peak is tilted **3° forward** due to local terrain slope

Questions:

1. What is the length of the shadow on flat ground? 
(Adjust the effective height using the 3° tilt.) 

2. If the valley floor rises by **100 m** over the shadow distance, 
how does this affect the final shadow length?

3. Explain the geometry clearly — this is a Tier 7 thinking challenge.



? Submit Your Attempt 
Thread title: 
Tier 7 Attempt — YourUsername — Challenge 003