`@@@@@`

`\frac{-3}{5} . 5/7 + \frac{-3}{5} . 3/7 + \frac{-3}{5} . 6/7`

`= \frac{-3}{5} . (5/7 + 3/7 + 6/7)`

`= \frac[-3}{5} . 14/7`

`= \frac{-3.14}{5.7}`

`= \frac{-3.7.2}{5.7}`

`= -6/5`

`@@@@@`

`1/3 . 4/5 + 1/3 . 6/5 - 4/3`

`= 1/3 (4/5+6/5) - 4/3`

`= 1/3 . 2 - 4/3`

`= 2/3 - 4/3`

`= \frac{2-4}{3}`

`= -2/3`

`@@@@@`