7 2/15 -(4 -3/715)+2 12/15

7 2/15 - ( 4 - 3 7/15) + 2 12/15 = 9,4 1) 4 - 3 7/15 = 3 15/15 - 3 7/15 = 8/15 2) 7 2/15 - 8/15 = 107/15 - 8/15 = 99/15 3) 99/15 + 2 12/15 = 99/15 + 42/15 = 141/15 = 9 6/15 = 9,4