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March 1, 2015

Posted by **Anonymous** on Wednesday, July 10, 2013 at 8:53pm.

Q(t) = Q0 · 2-(t/140)

If the amount of polonium left after 700 days is 45 mg, what was the initial amount present?

mg

- Calculus -
**Steve**, Thursday, July 11, 2013 at 10:40amQ0 2^-(700/140) = 45

Note that 700 days is 5 half-lives

So, 1/32 of Q0 is left

Q0 = 32*45 = 1440

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