(30,8+27,4)*0,9/(31,64-12,24)*1,2
1) 30.8+27,4=58,2 2) 58.2*0.9=52,38 3) 31.64-12.24=19.4 4) 19.4*1.2=23.28 5) 52.38:23.28=2.25