a) 7/12 - 4/12 + 9/12 = (7 - 4 + 9)/12 = 12/12 = 1
Ответ: 1
б) 5/29 + 12/29 - 14/29 + 7/29 = (5 + 12 - 14 + 7)/29 = 10/29
Ответ: 10/29
в) (17/47 + 12/47) - (41/47 - 37/47) = (17 + 12)/47 - (41 - 37)/47 = 29/47 - 4/47 = (29 - 4)/47 = 25/47
Ответ: 25/47
г) (19/24 + 23/24) - (9/24 + 13/24) = (19 + 23)/24 - (9 + 13)/24 = 42/24 - 22/24 = (42 - 22)/24 = 20/24 = 5/6
Ответ: 5/6