1/ -4/3 + 2/5 = (-20/15) + 6/15 = -14/15
2/ -2/5 - 5/6 = (-12/30) - 25/30 = -37/30
3/ -5.8/15 = -8/3
4/ \(-3\dfrac{2}{5}:7\dfrac{25}{8}=\dfrac{-17}{5}:\dfrac{81}{8}=\dfrac{-17}{5}.\dfrac{8}{81}=\dfrac{136}{405}\)
5/ 3/4 + (-1/3) - 5/18 = 27/36 + (-12/36) - 10/36 = 15/36 - 10/36 = 5/36
6/ 65/91 + (-33/55) = 65/91 + (-3/5) = 325/455 + (-273/455) = 52/455
7/ 4/9.(5/7 + 4/3) = 4/9.(15/21 + 28/21) = 4/9.43/21 = 172/189
8/ -5/2.(11/7 - 15/8) = -5/2.(88/56 - 105/56) = -5/2.(-17/56) = 85/112
9/ 7/3 + 1/2 - (-3/70) = 490/210 + 105/210 - (-9/210) = 595/210 - (-9/210) = 604/210
10/ 5/12 - 3/-16 + 3/4 = 5/12 - (-3/16) + 3/4 = 20/48 - (-9/48) + 36/48 = 29/48 + 36/48 = 65/48
