a) \(� - \frac{2}{3} = \frac{- 5}{12}\)

\(� = \frac{- 5}{12} + \frac{2}{3}\)

\(� = \frac{- 5}{12} + \frac{8}{12}\)

\(� = \frac{- 5 + 8}{12}\)

\(� = \frac{3}{12}\)

\(� = \frac{1}{4}\)

b) \(\frac{8}{5} : � = \frac{- 2}{3}\)

\(� = \frac{8}{5} : \left(\right. \&\text{nbsp}; \frac{- 2}{3} \left.\right)\)

\(� = \frac{8}{5} . \&\text{nbsp}; \left(\right. \&\text{nbsp}; \frac{3}{- 2} \left.\right)\)

\(� = \frac{- 12}{5}\)

c) \(1 - \frac{3}{7} . � = - \frac{2}{7}\)

\(\frac{3}{7} . � = 1 - \left(\right. - \frac{2}{7} \left.\right)\)

\(\frac{3}{7} . � = \frac{9}{7}\)

\(� = \frac{9}{7} : \frac{3}{7}\)

\(� = \frac{9}{7} . \frac{7}{3}\)

\(� = 3\)

a) \(� - \frac{2}{3} = \frac{- 5}{12}\)

\(� = \frac{- 5}{12} + \frac{2}{3}\)

\(� = \frac{- 5}{12} + \frac{8}{12}\)

\(� = \frac{- 5 + 8}{12}\)

\(� = \frac{3}{12}\)

\(� = \frac{1}{4}\)

b) \(\frac{8}{5} : � = \frac{- 2}{3}\)

\(� = \frac{8}{5} : \left(\right. \&\text{nbsp}; \frac{- 2}{3} \left.\right)\)

\(� = \frac{8}{5} . \&\text{nbsp}; \left(\right. \&\text{nbsp}; \frac{3}{- 2} \left.\right)\)

\(� = \frac{- 12}{5}\)

c) \(1 - \frac{3}{7} . � = - \frac{2}{7}\)

\(\frac{3}{7} . � = 1 - \left(\right. - \frac{2}{7} \left.\right)\)

\(\frac{3}{7} . � = \frac{9}{7}\)

\(� = \frac{9}{7} : \frac{3}{7}\)

\(� = \frac{9}{7} . \frac{7}{3}\)

\(� = 3\)

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