6 5/12×16/21=77/12*16/21

6 5\12 х 16\21= 77\12 х 16\216 5\12 х 16\21 = 77\12 х 16\21 = 88\18= 4 16\18 = 4 8\977\12 х 16\21= 88\18 = 4 16\18 = 4 8\94 8\9 = 4 8\9