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5) The half life of a radioactive isotope is 8 days. If 3.6 kg are present now, how much will be present in t days? How much will be present in 22 days?

closed with the note: no longer needed.

asked Sep 13, 2014 in PRECALCULUS by secretslocked Rookie
closed Sep 14, 2014 by secretslocked

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1 Answer

The half life of a radioactive isotope is 8 days.

Apply the formula .

Find k first.

Apply ln each side.

Subbstitute k in .

kg will be present in t days.

Subbstitute 22 days for t in .

0. 535 kg will be present in 22 days.

answered Sep 13, 2014 by david Expert
edited Sep 13, 2014 by bradely

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