Question

[Nguyễn Thái Bảo Châu]

1, \(\dfrac{-5}{7}\) . \(\dfrac{2}{11}\)  + \(\dfrac{-5}{7}\) . \(\dfrac{9}{11}\) + \(1\dfrac{5}{7}\)

2,\(-3\dfrac{4}{13}\) . \(15\dfrac{3}{41}\) + \(3\dfrac{4}{13}\) . \(2\dfrac{3}{41}\)

3, \(\dfrac{4}{5}\) . \(15\dfrac{1}{4}\)  - \(\dfrac{4}{5}\)   . \(15\dfrac{1}{3}\) + \(\dfrac{11}{30}\)

4,\(\dfrac{4}{20}\) + \(\dfrac{16}{42}\) + \(\dfrac{6}{15}\) - \(\dfrac{3}{5}\) + \(\dfrac{2}{21}\)  - \(\dfrac{10}{21}\) + \(\dfrac{3}{10}\)

Giúp mik nha. Cảm ơn