T varies inversely with the cube of W
[tex]T = k/W^3[/tex]
[tex]\frac{1}{9} = k/3^3[/tex]
[tex]k = \dfrac{3^3}{9} = 3[/tex]
[tex]W^3 = k/T[/tex]
[tex]W = \sqrt[3]{ k/T }[/tex]
When [tex]T=1/243[/tex]
[tex]W = \sqrt[3]{ 3/(1/243)}= \sqrt[3]{729} = 9[/tex]
