Given the expression:
[tex]P=\frac{RT}{nV}[/tex]You have to write the expression for V.
First, multiply both sides of the expression for nV to take the terms from the denominators place:
[tex]\begin{gathered} \text{nVP}=nV\cdot\frac{RT}{nV} \\ \text{nVP}=RT \end{gathered}[/tex]Second, divide both sides by nP so that the multiplication on the V-term is canceled:
[tex]\begin{gathered} \frac{\text{nVP}}{nP}=\frac{RT}{nP} \\ V=\frac{RT}{nP} \end{gathered}[/tex]