计算:(1)0.125×0.25×0.5×64(2)2006×2006×2006-2006×2006-2005(3)3.75×4.23×36-125×0.423×2.8(4)1030×0.125+44

题目简介

计算:(1)0.125×0.25×0.5×64(2)2006×2006×2006-2006×2006-2005(3)3.75×4.23×36-125×0.423×2.8(4)1030×0.125+44

题目详情

计算:
(1)0.125×0.25×0.5×64
(2)2006×2006×2006-2006×2006-2005
(3)3.75×4.23×36-125×0.423×2.8
(4)1030×0.125+44.3×12.5+262×1.25.
题型:解答题难度:中档来源:不详

答案

(1)0.125×0.25×0.5×64,
=0.125×0.25×0.2×(8×4×2),
=(0.125×8)×(0.25×4)×(0.5×2),
=1×1×1,
=1;

(2)2006×2006×2006-2006×2006-2005,
=2006×2006×(2006-1)-2005,(提前两个的公因数2006×2006)
=2006×2006×2005-2005,
=(2006×2006-1)×2005,(提公因数2005)
=(2006+1)×(2006-1)×2005,(前面括号里的用平方差公式因式分解)
=2007×2005×2005,
=8068190175;

(3)3.75×4.23×36-125×0.423×2.8,
=3.75×4.23×36-12.5×4.23×2.8,
=4.23×(3.75×36-12.5×2.8),
=4.23×(12.5×0.3×36-12.5×2.8),
=4.23×12.5×(0.3×36-2.8),
=4.23×12.5×(10.8-2.8),
=4.23×12.5×8,
=4.23×100,
=423;

(4)1030×0.125+44.3×12.5+262×1.25,
=103×1.25+443×1.25+262×1.25,
=(103+443+262)×1.25,
=808×1.25,
=(800+8)×1.25,
=800×1.25+8×1.25,
=1000+10,
=1010.

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