Ответ:\(0.72+3.018=3.738\);\(4-2.8=1.2\);\(1.8\cdot0.3=0.54\);\(5.4:6=0.9\);\(72:0.09=800\);\(9:4=2.25\).Ответ: 1) 3,738; 2) 1,2; 3) 0,54; 4) 0,9; 5) 800; 6) 2,25.