用乘法分配律简算,99×56+囗,囗里该填5699×56+56=(99+1)×56=100×56=5600
用乘法分配律简算,99×56+56=56(99+1)=56×100=5600即:□中应填56。
最好填56。99Ⅹ56+56=56X(99+1)=56X100=5600
99×56+囗,囗里该填5699×56+56=56×(99+1)=5600
5699×56+1×56=(99+1)×56=560099×56=5600-56=5544