1. (40+1)*(100+1)=40*100+100+40+1=4141
2. 907*(99+1)=90700
3. 5.6*1-0.01*5.6=5.6-0.056=5.544
4. 1200-(200-3)=1200-200+3=1003
5. 12*1/4+12*1/6+12*1/3=3+2+4=9
6. 580-2+300-2=880-4=876
7. (0.7+4.3)+(3.9+6.1)=5+10=15
8. 64/10=6.4
9. 9.56*18+0.44*18=18*(9.56+0.44)=18*10=180
10. 7.07+6.6=13.67
11. (7.28+4.72)-(3/8+5/8)=12-1=11
12. 2.5*4*(8*1.25)=10*10=100
4141
90700
5.544
1003
9
876
15
6.4
180
13.67
11
100
41*(100+1)=41*100+41*1=4141
1 =100*41+41=4141
2 =907*(99+1)=90700
3 =5.6*1-5.6*0.01=5.544
4 =1200-200+3=1003
5 =12*(1/4)+12*(1/6)+12*(1/3)=3+2+4=9
6 =578+-300-2=876
7 =(0.7+4.3)+(3.9+6.1)=15
8 =64/10=6.4
9 =18*(9.56+0.44)=18*10=180
10 =7.07+6.6=13.67
11 =7.28+4.72-(3/8+5/8)=11-1=10
12 =2.5*4*(8*1.25)=10*10=100
1 41*101=41*(100+1)=41*100+41=4141
2 907*99+907=907*(99+1)=907*100=90700
3 5.6*0.99=5.6*(1-0.01)=5.6-0.056=5.544
4 1200-197=1200-200+3=1003
5 12*(1/4+1/6+1/3)=12*1/4+12*1/6+12*1/3=3+2+4=9
6 578+298=578+300-2=876
7 0.7+3.9+4.3+6.1=(0.7+4.3)+(3.9+6.1)=5+10=15
8 16/2.5=16/10*4=6.4
9、95.6*1.8+0.44*18=95.6*1.8+4.4*1.8=1.8*(95.6+4.4)=180
10 10.47-3.4+6.6=10.47+3.2=13.67
11 7.28-3/8+4.72-5/8=(7.28+4.72)-(3/8+5/8)=12-1=11
12、2.5*32*1.25=(2.5*4)*(8*1.25)=10*10=100
1、41*101=41*(100+1)=41*100+1*41=4141 2、907*99+907=907*(99+1)=90700 3、5.6*0.99=5.6*(1-0.01)=5.6*1-5.6*0.01=5.544 4、1200-197=1200-(197+3)-3=1000-3=997 5、12*(1/4+1/6+1/3=3+2+4=9 6、578+298=578+(298+2)-2=878-2=876 7、0.7+3.9+4.3+6.1=(0.7+4.3)+(3.9+6.1)=15
8、16/2.5= 9、95.6*1.8+0.44*18=95.6*1.8+4.4*1.8=(95.6+4.4)*1.8=180 10、10.47-3.4+6.6=10.47-(3.4+6.6)=0.47 11、7.28-3/8+4.72-5/8=(7.28+4.72)-(3/8+5/8)=11
12、2.5*32*1.25=2.5*(4*8)*1.25=(2.5*4)*(1.25*8)=1000