oblicz tę dwa zadania dam najs

a) 3 1/9 - 1 5/9 + 2 4/9 = 28/9 - 14/9 + 22/9 = 36/9 = 4 b) 6 - (4 1/5 - 2 3/5) = 6 - (21/5 - 13/5) = 6/6 - 8/5 = 30/30 - 48/30 = -18/30 = -3/5