-5 1\6 + (7 1\9) + (-4 1\3) + (-7 1\9) = -5 1\6 + -4 1\3 + 7 1\9 + (-7 1\9) = (-5 1\6 + -4 1\3) + (7 1\9)+ (-7 1\9)) = ( -5 1\6 + -4 2\6 ) + 0 = -9 3\6 = -9 1\2
-5 1\6 + (7 1\9) + (-4 1\3) + (-7 1\9) = -5 1\6 + -4 1\3 + 7 1\9 + (-7 1\9) = (-5 1\6 + -4 1\3) + (7 1\9)+ (-7 1\9)) = ( -5 1\6 + -4 2\6 ) + 0 = -9 3\6 = -9 1\2