Question

-2/5 . (5/17 - 9/15) - 2/5 . (2/17 - 2/5)
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Answer 1

\(=\left(-\dfrac{2}{5}\right)\left(\dfrac{5}{17}-\dfrac{9}{15}+\dfrac{2}{17}-\dfrac{2}{5}\right)=\left(-\dfrac{2}{5}\right)\left(\dfrac{7}{17}-1\right)=\left(-\dfrac{2}{5}\right)\left(\dfrac{7-17}{17}\right)=\left(-\dfrac{2}{5}\right)\left(-\dfrac{10}{17}\right)=\dfrac{4}{17}\)

Answer 2

\(\dfrac{-2}{5}.\left(\dfrac{5}{17}-\dfrac{9}{15}\right)-\dfrac{2}{5}.\left(\dfrac{2}{17}-\dfrac{2}{5}\right)\)

\(=\dfrac{-2}{5}.\left(\dfrac{5}{17}-\dfrac{9}{15}+\dfrac{2}{17}-\dfrac{2}{5}\right)\)

\(=\dfrac{-2}{5}.\left(\dfrac{7}{17}-1\right)\)\(=\dfrac{-2}{5}.\dfrac{-10}{17}\)

\(=\dfrac{4}{17}\)

Answer 3

\(-\dfrac{2}{5}\left(\dfrac{5}{17}-\dfrac{9}{15}\right)-\dfrac{2}{5}\left(\dfrac{2}{17}-\dfrac{2}{5}\right)\)

\(=-\dfrac{2}{5}\left(\dfrac{5}{17}-\dfrac{3}{5}+\dfrac{2}{17}-\dfrac{2}{5}\right)\)

\(=-\dfrac{2}{5}\left(\dfrac{7}{17}-1\right)\)

\(=-\dfrac{2}{5}.\dfrac{-10}{17}=\dfrac{4}{17}\)