Answer:
- 33.75 minutes
- G(t) = 135(1/2)^(t/33.75)
- 51.42 grams
Step-by-step explanation:
Based on the given numbers, we know the decay factor is ...
8.25/132 = 1/16
in 135 minutes. We recognize 1/16 = (1/2)^4, so is 4 half-lives.
a) The half-life of goo is (135 min)/4 = 33.75 minutes
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b) A formula for the amount remaining could be ...
G(t) = 135(1/2)^(t/33.75)
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c) After 47 minutes, the amount remaining is ...
G(47) = 135(1/2)^(47/33.75) ≈ 51.42 . . . grams
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<em>Comment on the solution</em>
The general form of a decay equation can be ...
g(t) = (initial value)(decay factor)^(t/(decay time for the given factor))
For our G(t), we used a decay factor of 1/2 and the half-life time of 33.75 minutes.
