能巧算的要巧算:1 8.64/{64.8-(48.6-2.7*2)} 2 3.7*4.7+6.3*3.7-3.7 32.5*1.9+25*0.71+0.25*1.0(4) (12.5+12.5+12.512.5)*2.5

问题描述:

能巧算的要巧算:1 8.64/{64.8-(48.6-2.7*2)} 2 3.7*4.7+6.3*3.7-3.7 32.5*1.9+25*0.71+0.25*1.0
(4) (12.5+12.5+12.512.5)*2.5

(1) 8.64/{64.8-(48.6-2.7 *2)}=0.4(2) 3.7*4.7+6.3*3.7-3.7=3.7*(4.7+6.3-1)=3.7*10=37(3) 2.5*1.9+25*0.71+0.25*1=2.5*(1.9+7.1+0.1)=2.5*9.1=22.75(4) (12.5+12.5+12.5+12.5)*2.5=4*12.5*2.5=4*2.5*12.5==10*12.5...