А)1/2+1/2+1/2+1/2=4/2= 2Б)1/3+2/3+1/3+5/3= 9/3 = 3В)7/13+4/13+2/13= 13/13 = 1Г)1/96+5/96+11/96+31/96= 48/96 = 1/2Д)1/42+15/42+17/42+9/42= 42/42= 1Е)19/8+52/78+37/78+21/78= 19/8 + 2/3 + 37/78 + 7/26 =(19*39 + 2 * 104 + 37 * 4 + 7 * 12)/312 = 741/312 + 208/312 + 148/312 + 84/312 = 1181/312=3 245/312если в условии опечатка и там 19/78 то ответ так :19/78 + 52/78 + 37/78 + 21/78 = 129/78 = 43/26 = 1 17/26