3a/5b=2/3 b/a=?

Dau coroana!!

[tex] \frac{3a}{5b} = \frac{2}{3} [/tex]

[tex] \frac{3}{5} \times \frac{a}{b} = \frac{2}{3} [/tex]

[tex] \frac{a}{b} = \frac{2}{3} \div \frac{3}{5} [/tex]

[tex] \frac{a}{b} = \frac{2}{3} \times \frac{5}{3} [/tex]

[tex] \frac{a}{b} = \frac{2 \times 5}{3 \times 3} [/tex]

[tex] \frac{a}{b} = \frac{10}{9} [/tex]

[tex]{(\frac{a}{b})}^{-1}=\frac{b}{a}=\frac{9}{10}[/tex]

a/b=10/9 ⇒
b/a=9/10
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