快乐实践
1、2.5×6.9×0.04=6.9×(2.5×0.04)
4.66×6.5+6.5×5.34=6.5×(4.66+5.34)
1.25×(8+0.8)=1.25×8+1.25×0.8
2、12.5×27×0.8
=12.5×(27×0.8)
=12.5×21.6
270
9.8×7.7+9.8×2.3
=(9.8×7.7)+(9.8×2.3)
=75.46+(9.8×2.3)
=75.46+22.54
=98
6.23×10.1=62.923
0.125×2.5×40×0.8
=(0.125×2.5)×40×0.8
=(0.3125×40)×0.8
=12.5×0.8
=10
0.89×99=88.11
2.8×3.6=9