Hello
If Susan takes 300mg of a drug twice daily
[tex]300mg[/tex]But she was given 75mg tab and takes the drug twice daily
Let's divide her daily dose by the numbers of time she takes it
[tex]\frac{300mg}{2}=150mg[/tex]This implies she takes 150mg in the morning. To find the number of tablets that will amount to 150mg would be
[tex]\begin{gathered} 1\text{tab}=75mg \\ \text{xtab}=150mg \end{gathered}[/tex]Cross multiply both sides and solve for x
[tex]\begin{gathered} x\times75=1\times150 \\ 75x=150 \\ \frac{75x}{75}=\frac{150}{75} \\ x=2 \end{gathered}[/tex]From the calculations above, Susan has to take 2 tablets of her medication in the morning daily.