12*5-4+56:6+456*786:43
12*5-4+56:6+456*786:43=8400 76/129 12*5=60 56:6=9 1/3 456*486=358416 358416:43=8335 11/43 60-4=56 56+9 1/3=65 1/3 65 1/3+8335 11/43= 8400+(1/3+11/43)=8400+(1*43/129+11*3/129)=8400 76/129