56乘99=()乘(100)-()=()-()=()
问题描述：
56乘99=()乘(100)-()=()-()=()
答
57x98-56x99 =57x100-57x2-56x100+56 =56x100+100-56x2-2-56x100+56 =100-56-2 =42 (57-56)×98-56=42
答
56乘99=56乘100-56=5600-56=5544
答
56乘99=(56)乘(100)-(56)=(5600)-(56)=(5544)