6 2/25 + 7 23/25 - 4 1/40

б) 20 1/19-4 12/19 - 5 17/19

в) (6 5/24+7 19/24) - 6 19/23-5 9/23

А) 13 25/25-4 1/40 = 14-4 1/40 = 13 40/40-4 1/40=11 39/40

б) 20 1/19 - (4 12/19+5 17/19) = 20 1/19-9 29/19 = 20 1/19-10 10/19=19 20/19-10 10/19=9 10/19

в) 13 24/24-6 19/23 - 5 9/23 = 14 - (6 19/23+5 9/23) = 14-11 24/23=14-12 1/23=13 23/23-12 1/23=1 22/23