marina779 5*4007=5*(4000+7)=
5*4000+5*7=20000+35=
20035
5*50020=5*(50000+20)=
5*50000+5*20=250000+
100=250100
5*50200=5*(50000+200)=
5*50000+5*200=
250000+1000=251000