79 (3\4+1\2-3\8): (1 5\12-9\16+1 1\3)+(2,48: 0,4-3,2): (4,19+2,7*0,3)=

(3\4+1\2-3\8):(1 5\12-9\16+1 1\3)+(2,48:0,4-3,2):(4,19+2,7*0,3)

(3\4+1\2-3\8) = 6/8 + 4/8 - 3/8 = 7/8
(1 5\12-9\16+1 1\3) = 17/12 - 9/16 + 4/3 = 68/48 - 27/48 + 64/48 = 105/48
(2,48:0,4-3,2) = 6,2 - 3,2 = 3
(4,19+2,7*0,3) = 4,19 + 0,81 = 5

7/8 : 105/48 + 3 : 5 = 42/105 + 3/5 = 42/105 + 63/105 = 105/105 = 1

(3\4+1\2-3\8):(1 5\12-9\16+1 1\3)+(2,48:0,4-3,2):(4,19+2,7*0,3) = 1