а) 2/3 + 4/7 = (27 + 43)/(3*7) = 14/21 + 12/21 = 26/21 = 1 5/21
б) 3 7/8 + 2 5/12 = 3 + 2 + 7/8 + 5/12 = 5 + 12 + 21/24 + 10/24 = 7 31/24 = 8 7/24
в) 5 11/12 - 3 7/18 = 5 - 3 + 11/12 - 7/18 = 2 + 198/216 - 126/216 = 2 72/216 = 2 1/3
а) 2/3 + 4/7 = (27 + 43)/(3*7) = 14/21 + 12/21 = 26/21 = 1 5/21
б) 3 7/8 + 2 5/12 = 3 + 2 + 7/8 + 5/12 = 5 + 12 + 21/24 + 10/24 = 7 31/24 = 8 7/24
в) 5 11/12 - 3 7/18 = 5 - 3 + 11/12 - 7/18 = 2 + 198/216 - 126/216 = 2 72/216 = 2 1/3