SOLUTION: A certain radioactive isotope has a half life of approximately 850 years . How many years to the nearest year would be required for a given amount of this isotope to decay to 45% o

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Question 864218: A certain radioactive isotope has a half life of approximately 850 years . How many years to the nearest year would be required for a given amount of this isotope to decay to 45% of that amount
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Q%28t%29+=+Q%5B0%5De%5E%28-kt%29+ first find k
ln%28.5%29%2F%28-850%29 = k = .00082
then find
+ln%28.45%29%2F%28-.0008%29 = t = 998 yrs