Iodine-131 is used in treatment of thyroid disorder. This isotope has a half life of 8.04 days, what percentage of an initial sample is left after 30 days?(adsbygoogle = window.adsbygoogle || []).push({});

having done, the initial calculations by taking 30 divided by 8.04 to find how many hl will have passed i take the number and i take the mass number divided by the amount of hl that has passed times 100 but my answers dun match the answer in the book.

where did i go wrong?

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# Half life question

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