SOLUTION: What is the Half life of carbon if it takes 11,400 years to decay to 25% of its original mass?

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Question 1070350: What is the Half life of carbon if it takes 11,400 years to decay to 25% of its original mass?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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What is the Half life of carbon if it takes 11,400 years to decay to 25% of its original mass?
:
Let initial amt = 1
then
.75 = the amt after 11400 yrs
:
let h = the half life of the substance
:
1*2^(-11400/h) = .25
-11400%2Fh*ln(2) = ln(.25)
-11400%2Fh = ln%282%29%2Fln%28.25%29
-11400%2Fh = -.5
h = 11400 * .5
h = 5700 years is the half life