1) 5,1(12)+128/330 = 5 111\990 + 128\330 = 5 495\990 = 5 1\2.
2) 2,3(72)-41/110 = 2 369\990 - 41\110 = 2.
3) 2,(8)+1 2/3 = 2 8\9 + 1 2\3 = 2 8\9 + 1 6\9 = 4 5\9.
4) 3,16(54)-18/275 = 3 819\4950 - 18\275 = 3 495\4950 = 3,1.