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ira [324]
3 years ago
10

A toxic radioactive substance with the density of 4 mg/cm² is detected in the been detected in the ventilating ducts that was us

ed 35 years ago. if the half-life of substances 20 years what is the density of a substance when it was deposited 35 years ago
Mathematics
1 answer:
Kruka [31]3 years ago
8 0
The formula for half-life is:

A = P(0.5)^{t/h}

A is the amount remaining, P is the initial amount, t is the time that has passed, and h is the half-life of the substance.  Plug in the values that you know and solve:

4 = P(0.5)^{35/20} \\ \\ 4 = P(0.5)^{1.75} \\ \\ P = \frac{4}{0.5^{1.75}} \\ \\ P \approx 13.4543426441

Rounded to the nearest whole number, the density of the substance was about 13<span>mg / cm².</span>
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