1) (5*11/12+8*7/15)+(16*7/24-9*3/56)=(55/12+56/15)+(2*7/3-27/56)=499/60+(14/3-27/56)=499/60+703/168=10501/840
2)(3*13/14+15/6)+27*13/30-(15*5/12-12*13/20)=(39/14+15/6)+9*13/10-(5*5/4-3*13/5)=37/7+117/10-(25/4-39/5)=37/7+117/10+31/20=519/28
3)4*2/5+3*3/4-3*2/15+11/3=2/5*3*3-2/5+11/3=18/5-2/5+11/3=103/15
125 / 5 = 25
25 * 4 = 100
100 * 3,765 = 376,5
189 / 7 = 27
27 * 6 = 162
162 / 2 = 81
160 + 376,5 -81 = 455,5