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A radioactive substance has a half-life of 3 days. If a mass of 1.55g of this substance ...

A radioactive substance has a half-life of 3 days. If a mass of 1.55g of this substance is left after decaying for 15 days, determine the original value of the mass
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  • A 49.6g
  • B 37.2g
  • C 24.8g
  • D 12.4g
Correct Answer: Option A
Explanation:
\(1 \to \frac{1}{2} \to \frac{1}{4} \to \frac{1}{8} \to \frac{1}{16} \to \frac{1}{32}\)
\(\frac{1}{32} = 1.55g\)
1 = 1.55 x \(\frac{32}{1} = 49.6g\)

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