As given by the question
There are given that the equation
[tex]\frac{1}{4}(px-16)=64[/tex]Now,
multiply by 4 on both sides of the equation
So,
[tex]\begin{gathered} \frac{1}{4}(px-16)=64 \\ \frac{1}{4}(px-16)\times4=64\times4 \\ px-16=256 \end{gathered}[/tex]Then,
Add 16 on both sides of the equation:
[tex]\begin{gathered} px-16=256 \\ px-16+16=256+16 \\ px=272 \\ x=\frac{272}{p} \end{gathered}[/tex]Hence, the correct option is b.