Question

Answer 1

B8:

a.

\(=-\dfrac{4}{7}+\dfrac{3}{5}+\left(-\dfrac{1}{42}\times-\dfrac{6}{5}\right)\)

\(=-\dfrac{20}{35}+\dfrac{21}{35}+\dfrac{1}{35}=\dfrac{-20+21+1}{35}=\dfrac{2}{35}\)

b.

\(=\dfrac{2}{9}.\left[-\dfrac{4}{45}:\left(\dfrac{3}{15}-\dfrac{2}{15}\right)+\dfrac{5}{3}\right]+\dfrac{5}{27}\)

\(=\dfrac{2}{9}.\left(\dfrac{-4}{45}:\dfrac{1}{15}+\dfrac{5}{3}\right)+\dfrac{5}{27}\)

\(=\dfrac{2}{9}\left(\dfrac{-4}{3}+\dfrac{5}{3}\right)+\dfrac{5}{27}\)

\(=\dfrac{2}{9}\times\dfrac{1}{3}+\dfrac{5}{27}=\dfrac{2}{27}+\dfrac{5}{27}=\dfrac{7}{27}\)