Question

Answer 1

1: \(=\dfrac{8}{21}-\dfrac{5}{4}+\dfrac{3}{14}+\dfrac{13}{21}+\dfrac{1}{4}=\dfrac{3}{14}\)

2: \(=\dfrac{5}{8}\left(2+\dfrac{2}{5}-1-\dfrac{1}{3}\right)=\dfrac{5}{8}\cdot\dfrac{16}{15}=\dfrac{2}{3}\)

3: \(=\left(\dfrac{4}{9}-\dfrac{3}{5}+\dfrac{5}{9}+\dfrac{1}{5}\right):\dfrac{6}{5}=\left(1-\dfrac{2}{5}\right)\cdot\dfrac{5}{6}=\dfrac{4}{5}\cdot\dfrac{5}{6}=\dfrac{2}{3}\)

4: \(=\dfrac{6}{7}\cdot\dfrac{-3}{26}-\dfrac{6}{7}:\dfrac{-6}{10}\)

\(=\dfrac{6}{7}\left(-\dfrac{3}{26}+\dfrac{5}{3}\right)=\dfrac{121}{91}\)