10*(920-20)= 8*(720-700)= 184*100-300= 100*391-3000=
10·(920-20)=10·900=9000 8·(720-700)=8·20=160 184·100-300=18400-300=18100 100·391-3000=39100-3000=36100
10*(920-20)=10*900=9000 8*(720-700)=8*20=160 184*100-300=18400-300=18100 100*391-3000=39100-3000=36100