36.9-10.47+3.1+0.53 2.5*3.2*1.25 9.9*34 3.12+3.12*99 3.12+6.88*1.2用简便方法计算
问题描述:
36.9-10.47+3.1+0.53 2.5*3.2*1.25 9.9*34 3.12+3.12*99 3.12+6.88*1.2用简便方法计算
答
解36.9-10.47+3.1-0.53 =(36.9+3.1)-(10.47+0.53)=40-11=29 2.5*3.2*1.25 =2.5*4*8*1.25 =(2.5*4)*(8*1.25 )=10*10=1009.9*34 =(10-0.1)*34 =10*34-0.1*34=340-3.4=336.63.12+3.12*99 =3.12*(1+99)=3.12...