sprawdzcie czy dobrze 4/5+2.25=0.8+2.25=3.o5 1i3/4+0.3=1.75+0.3=2.05 2i1/2*0.4=2.5*0.4=1 3/5*1.1=0.6*1.1=0.66 1i3/5-0.6=1.6-0.6=1 11/20-0.45=0.55-0.45=0.1 2/5:0.2=0.4:0.2=2 1.2:3/5=1.2:0.6=2