简便计算 1:0.25×125×6.4=?2:14.7×0.21+1.47×12.9-147×0.05=?要求运算过程急.

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简便计算 1:0.25×125×6.4=?2:14.7×0.21+1.47×12.9-147×0.05=?要求运算过程急.
简便计算 1:0.25×125×6.4=?2:14.7×0.21+1.47×12.9-147×0.05=?
要求运算过程
急.

简便计算 1:0.25×125×6.4=?2:14.7×0.21+1.47×12.9-147×0.05=?要求运算过程急.
(1)0.25×125×6.4=0.25*25*5*0.4*4*4=0.25*4*25*4*0.4*5=200
(2)14.7*(0.21+1.29-0.5)=14.7*1=14.7

1:0.25×125×6.4=0.25*125*4*1.6=(0.25*4)*(125*1.6)=1*195=195
2:14.7×0.21+1.47×12.9-147×0.05=14.7*0.21+14.7*1.29-14.7*0.5
=14.7*(0.21+1.29-0.5)=14.7*1=14.7

第一个=0.25*125*(6+0.4)=25*1.25*6+25*1.25*0.4=150*1.25+10*1.25=160*1.25=100*1.25+60*1.25=125+75=200,第二个=1.47*2.1+1.47*12.9-1.47*5=1.47*(2.1+12.9-5)=1.47*10=14.7

1:0.25*4*1.6*125=1.6*125=4*125*0.4=500*0.4=200
2:(2.1+12.9-5)*14.7=10*14.7=147