Question

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a) \(\dfrac{1}{5}:\dfrac{-7}{15}-\dfrac{-2}{7}\)

b) \(\dfrac{5}{6}-\dfrac{2}{3}+\dfrac{1}{4}\)

Answer 1

a) \(\dfrac{1}{5}\) : \(\dfrac{-7}{15}\) - \(\dfrac{-2}{7}\)

= (\(\dfrac{1}{5}\): \(\dfrac{-7}{15}\)) - \(\dfrac{-2}{7}\)

= \(\dfrac{-3}{7}\) - \(\dfrac{-2}{7}\)

= \(\dfrac{-1}{7}\)

b) \(\dfrac{5}{6}\) - \(\dfrac{2}{3}+\dfrac{1}{4}\)

= \(\left(\dfrac{5}{6}-\dfrac{2}{3}\right)+\dfrac{1}{4}\)

= \(\left(\dfrac{5}{6}-\dfrac{4}{6}\right)+\dfrac{1}{4}\)

= \(\dfrac{1}{6}+\dfrac{1}{4}\)

= \(\dfrac{5}{12}\)