The mass of the radioactive sample at the beginning of the 8th day of the experiment a_13=310.7.
In a lab experiment, the decay of a radioactive isotope is being observed.
At the beginning of the first day of the experiment, the mass of the substance was 1300 grams and the mass decreased by 6% per day.
[tex]a_n=a_1r^{n-1}[/tex]
Use the given value in the formula so we get,
[tex]a_{13}=1100(0.9)^{13-1}[/tex]
Simplify the given term
[tex]a_{13}=310.7[/tex]
Therefore, The mass of the radioactive sample at the beginning of the 8th day of the experiment a_13=310.7.
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