Answer :
Harper takes 623 milligrams of an antibiotic.
Every hour, her body breaks down 13% of the drug.
First hour : 13 % of the total.
[tex]\begin{gathered} 13\text{ \% of 623 milligrams} \\ \frac{13}{100}\times623=80.99\text{milligrams} \end{gathered}[/tex]After six hours , the body would have break
multipy the first hour result by six
[tex]80.99\times6=485.94milligrams[/tex]How much will be left after 6 hours, subtract the result from the total:
[tex]623-485.94=137.06\text{milligrams}[/tex]Therefore the antibiotics left will be 137.1 milligrams to the nearest tenth.
[tex]137.1\text{milligrams}[/tex]