[tex] \frac{2a}{3b} = \frac{8}{9} [/tex]
[tex] \frac{2}{3} \times \frac{a}{b} = \frac{8}{9} [/tex]
[tex] \frac{a}{b} = \frac{8}{9} \div \frac{2}{3} [/tex]
[tex] \frac{a}{b} = \frac{8}{9} \times \frac{3}{2} [/tex]
[tex] \frac{a}{b} = \frac{4}{3} \times \frac{1}{1} [/tex]
[tex] \frac{a}{b} = \frac{4}{3} \times 1[/tex]
[tex] \frac{a}{b} = \frac{4}{3} [/tex]
[tex] { (\frac{a}{b}) }^{ - 1} = \frac{b}{a} = \frac{3}{4} [/tex]
