一.3.9x1.4÷0.35二.0.13x102三.0.5x2.33x4四.9.07-22.78÷34 .能用简便算法的
2个回答

3.9x1.4÷0.35 0.13*102 0.5*2.33*4 9.07-22.78÷34

=3.9*2*0.7÷0.7÷0.5 =0.13*(100+2) =0.5*4*2.33 =9.07-0.67

=7.8÷1/2 =0.13*100+0.13*2 =2*2.33 =8.4

=7.8*2 =13+0.26 =4.66

=15.6 =13.26