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99999×77778+33333×66666巧算

来源:学生作业帮 编辑:百度作业网作业帮 分类:数学作业 时间:2024/06/22 21:50:59
99999×77778+33333×66666巧算
99999×77778+33333×66666巧算
99999×77778+33333×66666
=99999×77778+33333×3×22222
=99999×77778+99999×22222
=99999×(77778+22222)
=99999×100000
=9999900000
再问: 17.5+17.5×1.74÷【0.1-0.04】巧算
再答: 17.5+17.5×1.74÷【0.1-0.04】

=17.5+17.5×1.74÷0.06

=17.5+17.5×29
=17.5x(1+29)
=17.5x30
=525
再问: {【12.5+1.25+0.125】×80-999}÷0.03巧算
再答: {【12.5+1.25+0.125】×80-999}÷0.03

={【12.5+12.5/10+12.5/100】×80-999}÷0.03

={12.5x(1+1/10+1/100)x80-999}÷0.03
={12.5x80x(1+1/10+1/100)-999}÷0.03
={1000x(1+1/10+1/100)-999}÷0.03
={1000+100+10-999}÷0.03
={1000-999+100+10}÷0.03
={1+100+10}÷0.03
=111÷0.03
=3700