А) 9 5/21 - (10 2/3 - 3 5/28) =

б) 6 132/15+3 7/12 - 4 9/10=

в) 12+3 3/8 - 1 5/6=

г) 7 8/15 + (5 7/10 - 4) =

А) 9 5/21 - (10 2/3 - 3 5/28) = 9 5/21 - ((10-3) + 41/84)) = (9-7) + 5/21-41/84=-2 1/4

б) 6 132/15+3 7/12 - 4 9/10 = (6+3-4) + (264+35-54/60) = 5 49/12

в) 12+3 3/8 - 1 5/6 = (12+3-1) + (9-20/24) = - 14 11/24

г) 7 8/15 + (5 7/10 - 4) = (7+5-4) + (16+21/30) = 8 37/30