-(10.74 - 6 8/9)-(0.26- 3 1/9) = -10.74 + 6 8/9 - 0.26 + 3 1/9 = (-10.74 - 0.26) + (6 8/9+ 3 1/9) = -11 + 10 = -1
-(10.74 - 6 8/9)-(0.26- 3 1/9) = -10.74 + 6 8/9 - 0.26 + 3 1/9 = (-10.74 - 0.26) + (6 8/9+ 3 1/9) = -11 + 10 = -1