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Shyne_06
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Math help..10 pts for best answer?
The Half-life Kinnium, a radioactive substance, is 1260 years. What percent of a present amount of Kinnium will remain after 300 years?
I can't figure it out..help me please
1 Answer
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- Anonymous1 decade agoFavorite Answer
A(t) = A(t=0) exp(-a t)
A/A0 = exp(-a t)
1/2 = exp(-a 1260)
ln 2 = a 1260
a = (ln 2)/1260
A(t=300)/A0 = exp(-(ln 2)/1260 * 300)
as a percentage:= 100 * A(t=300)/A0 %
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