SOLUTION: At the beginning of an experiment, a scientist has 224 grams of radioactive goo. After 270 minutes, her sample has decayed to 14 grams. 1)What is the half-life of the goo in minu

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Question 848734: At the beginning of an experiment, a scientist has 224 grams of radioactive goo. After 270 minutes, her sample has decayed to 14 grams.
1)What is the half-life of the goo in minutes?
2)Find a formula for G(t), the amount of goo remaining at time t.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
At the beginning of an experiment, a scientist has 224 grams of radioactive goo. After 270 minutes, her sample has decayed to 14 grams.
A(t) = ab^t
14 = 224*b^270
0.0625 = b^270
b = 0.0625^(1/270)
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1)What is the half-life of the goo in minutes?
Solve 0.0625^(t/270) = 1/2
(t/270)log(0.0625) = log(0.5)
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t/270 = 0.25
t = 67.5 minutes (that is the half-life)
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2)Find a formula for G(t), the amount of goo remaining at time t.
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A(t) = 224*0.0625^(t/270)
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Cheers,
Stan H.