SOLUTION: In the formula A(t) = A0ekt, A is the amount of radioactive material remaining from an initial amount A0 at a given time t, and k is a negative constant determined by the nature

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Question 250173: In the formula A(t) = A0ekt, A is the amount of radioactive material
remaining from an initial amount A0 at a given time t, and k is a negative
constant determined by the nature of the material. A certain radioactive
isotope decays at a rate of 0.3% annually. Determine the half-life of this
isotope, to the nearest year.
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
.997 = e^k ___ ln(.997) = k

.5 = e^[t ln(.997)]

ln(.5) = t ln(.997)

[ln(.5)] / [ln(.997)] = t

231 = t (approx)