Выполните действие 1)8+4/21; 2)5 16/19+3 5/19 3)7 7/16-3 3/16 4)10 12/17+5 4/17-3 3/17

1) 8 + 4 / 21 = 168/21 + 4/21 = 172/21 = 8 4/21
2) 5 16/19 + 3 5/19 = 8 21/19 = 9 2/19
3) 7 7/16 - 3 3/16 = 4 4/16 = 4 1/4
4) 10 12/17 + 5 4/17 - 3 3/17 = 12 13/17