=21.1×55.50*100+44.50*100×78.9+55.5×7890+2110×44.5
=55.5*(2110+7890)+44.5*(7890+2110)
=(55.5+44.5)*(2110+7890)
=100*10000
=1000000
数学简便算法：21.1×5550+4450×78.9+55.5×7890+2110×44.5
=21.1×55.50*100+44.50*100×78.9+55.5×7890+2110×44.5
=55.5*(2110+7890)+44.5*(7890+2110)
=(55.5+44.5)*(2110+7890)
=100*10000
=1000000