821+822+823+825+826+827=________×________=________.
824 6 4944
分析:821=824-3,822=824-2,823=824-1,825=824+1,826=824+2,827=824+3;由此把所有的加數(shù)變成含有824的算式,再運用加法結(jié)合律簡算,然后根據(jù)乘法的意義求解.
解答:821+822+823+825+826+827,
=(824-3)+(824-2)+(824-1)+(824+1)+(824+2)+(824+3),
=(824+824+824+824+824+824)+(3+2+1-1-2-3),
=824+824+824+824+824+824,
=824×6,
=4944.
故答案為:824,6,4944.
點評:本題主要是根據(jù)乘法的意義:求幾個相同加數(shù)和的簡便運算進行求解.