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Lau16
[tex] \frac{3- \frac{2}{3} }{ \frac{4}{3}*7 } [/tex] = [tex] \frac{ \frac{9}{3}- \frac{2}{3} }{ \frac{28}{3} } = \frac{ \frac{7}{3} }{ \frac{28}{3} } = \frac{7}{3}* \frac{3}{28} = \frac{21}{84} = \frac{1}{4} [/tex]

[tex] \frac{ \frac{2}{3} }{ \frac{5}{6} } - \frac{2}{5} = \frac{2}{3} * \frac{6}{5} - \frac{2}{5} = \frac{12}{15} - \frac{6}{15} = \frac{6}{15} = \frac{2}{5} [/tex]

[tex] \frac{ - \frac{3}{4} + \frac{1}{2} }{ \frac{2}{5} - \frac{5}{2} } = \frac{ - \frac{6}{8} + \frac{4}{8} }{ \frac{4}{10} - \frac{25}{10} } = \frac{ - \frac{2}{8} }{ \frac{-21}{10} } = - \frac{2}{8} * (- \frac{10}{21} ) = \frac{20}{168} = \frac{10}{84} = \frac{5}{42} [/tex]
Eliott78
a][tex] \frac{3 -\frac{2}{3} }{ \frac{4}{3} * 7} = \frac{ \frac{9}{3}- \frac{2}{3} }{ \frac{28}{3} } = \frac{ \frac{7}{3}}{ \frac{28}{3}} = \frac{7}{3} * \frac{3}{28}= \frac{21}{84}= \frac{7}{28} [/tex]

b][tex] \frac{ \frac{2}{3} }{ \frac{5}{6} } - \frac{2}{5} = \frac{2}{3} * \frac{6}{5} = \frac{12}{15}- \frac{6}{15}= \frac{2*3}{3*5} = \frac{2}{5} [/tex]

c][tex] \frac{ -\frac{3}{4} + \frac{1}{2}}{ \frac{2}{5} - \frac{5}{2}} = \frac{ -\frac{3}{4}+ \frac{2}{4} }{ \frac{4}{10}- \frac{25}{10} } = \frac{- \frac{1}{4} }{- \frac{21}{10} }= - \frac{1}{4} * -\frac{10}{21} = \frac{10}{84}= \frac{5}{42} [/tex]

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