First we need to transform into a fraction 11 1/4
[tex]11\text{ }\frac{1}{4}=\frac{45}{4}[/tex]the equation is
[tex]\frac{45}{4}+9d>72[/tex]then we clear d
[tex]\begin{gathered} 9d>72-\frac{45}{4} \\ 9d>\frac{243}{4} \\ d>\frac{27}{4} \\ d>6.75 \end{gathered}[/tex]