Question

2.9*0.45+0.29*4.2+0.029*13 3.84*9.6+0.96*61.6

简便运算
2.9*0.45+0.29*4.2+0.029*13 3.84*9.6+0.96*61.6

Answer 1

2.9*0.45+0.29*4.2+0.029*13
=2.9*0.45+2.9*0.42+2.9*0.13
=2.9*(0.45+0.42+0.13)
=2.9*1
=2.9

3.84 × 9.6 + 0.96 × 61.6
= 3.84 × 9.6 + 9.6 × 6.16
= 9.6 × (3.84 + 6.16)
= 9.6 × 10
= 96

Answer 2

2.9*0.45+0.29*4.2+0.029*13
=2.9×0.45+2.9×0.42+2.9×0.13
=2.9×（0.45+0.42+0.13）
=2.9×1
=2.9

应用积不变的规律，再用乘法分配律

3.84*9.6+0.96*61.6
=3.84×9.6+6.16×9.6
=9.6×（3.84+6.16）
=9.6×10
=96