SOLUTION: A scientist begins with 250 grams of a radioactive substance. After 250 minutes, the sample has decayed to 32 grams. Write an exponential equation f(t)representing this situation.

Question 1130123: A scientist begins with 250 grams of a radioactive substance. After 250 minutes, the sample has decayed to 32 grams. Write an exponential equation f(t)representing this situation. (Let f be the amount of radioactive substance in grams and t be the time in minutes.)
My previous answers have been:
250*2 (-t/h)
250*(.5)^t
Found 2 solutions by stanbon, josgarithmetic:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A scientist begins with 250 grams of a radioactive substance. After 250 minutes, the sample has decayed to 32 grams. Write an exponential equation f(t)representing this situation. (Let f be the amount of radioactive substance in grams and t be the time in minutes.)
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y = a*b^t
32 = 250*b^t
32 = (250 grams)*k^(250 min)
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Cheers,
Stan H.

Answer by josgarithmetic(39618) (Show Source): You can put this solution on YOUR website!

AMP Parsing Error of [250*log((b))=log((16/125)]: Invalid function: opening bracket expected at /home/ichudov/project_locations/algebra.com/templates/Algebra/Expression.pm line 88. .

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half-life:

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