Вычислите а)1/3- 2/9 б)3/20 + 5/8 в)7/18+1/6-0,2
А)1/3- 2/9 = 3/9 - 2/9 = 1/9 б)3/20 + 5/8 = 6/40 + 25/40 = 31/40 в)7/18+1/6-0,2 = 7/18 + 3/18 - 1/5 = 10/18 - 1/5 = 5/9 - 1/5 = 25/45 - 9/45 = 16/45