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TIER 6 — CHALLENGE 003 — The Chemical Decay Sample - Printable Version

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TIER 6 — CHALLENGE 003 — The Chemical Decay Sample - Leejohnston - 11-14-2025

[border]TIER 6 — Structured Problem Solving[/border]

Tier 6 — Challenge 003 — The Chemical Decay Sample

A chemical breaks down over time following the function:

M(t) = 120 · (0.85)^t

Where:
• M(t) = mass remaining (grams) 
• t = number of hours 

Questions:

1. How much mass remains after **6 hours**? 
2. After how many hours will the mass reach **50 grams**? 
(You may solve using logarithms or iterative reasoning.) 
3. What percentage of the chemical decays each hour?

Show your modelling clearly.



? Submit Your Attempt 
Thread title: 
Tier 6 Attempt — YourUsername — Challenge 003