(78.6-0.786×25+75%×21.4)÷15×2010
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解:(78.6-0.786×25+75%×21.4)÷15×2010,
=[(78.6-78.6×0.25)+0.75×21.4]÷15×2010,
=[78.6×(1-0.25)+0.75×21.4]÷15×2010,
=[78.6×0.75+0.75×21.4]÷15×2010,
=[(78.6+21.4)×0.75]÷15×2010,
=75÷15×2010,
=5×(2000+10),
=10000+50,
=10050.
解析分析:通过观察,根据数字特点,把原式变为[(78.6-78.6×0.25)+0.75×21.4]÷15×2010,中括号内两次运用乘法分配律简算,原式为75÷15×2010,把2010看作2000+10,再次运用乘法分配律简算.
点评:完成本题,应注意分析式中数据,运用合适的运算定律进行简算.