58.5×8.1＋11×1.25＋71×1.9＝ 要简便计算的步骤
问题描述：
58.5×8.1＋11×1.25＋71×1.9＝
要简便计算的步骤
答
主要是58.5*8.1比较难处理，后面都好办！
1.25*11可以变成1.25*（10+1）
71*1.9可以71*2-7.1
答
55.5*(10-1.9)+(10+1)*1.25+71*1.9
=555-55.5*1.9+12.5+1.25+71*1.9
=555+1.9(71-55.5)+12.5+1.25
=555+1.9*25.5+12.5+1.25
=555+(2-0.1)*25.5+12.5+1.25
=555+51-2.55+12.5+1.25
=606+13.75-2.55
=606+11.2
=617.2
答
55.5*(10-1.9)+(10+1)*1.25+71*1.9
=555-55.5*1.9+12.5+1.25+71*1.9
=555+1.9(71-55.5)+12.5+1.25
=555+1.9*25.5+12.5+1.25
=555+(2-0.1)*25.5+12.5+1.25
=555+51-2.55+12.5+1.25
=606+13.75-2.55
=606+11.2
=617.2
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