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September 17, 2014

September 17, 2014

Posted by **Roseanne** on Sunday, October 21, 2012 at 2:34pm.

- math -
**Steve**, Sunday, October 21, 2012 at 3:17pmafter the theft, there was 1 g left.

If the half-life is n days, then the fraction left after t days is

(1/2)^(t/n)

so, solve this for n:

0.1 = (1/2)^(8/n)

ln 0.1 = (8/n) ln 0.5

ln .1/ln .5 = 8/n

n = 8 * ln .5/ln .1

n = 2.4 days

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