w[i_,t_]=a/(1+(a/x[i] -1) E^(-c t)); a=100; c=0.5; x[i_]=5+i 40; abb=Plot[Evaluate[Table[w[i,t],{i,0,4}]],{t,0,10}, PlotRange->{0,200},AxesLabel->{"t","x"},ImageSize->{400,300}];