Question

(5) 4.2*8.8+2.2*1.2

Answer 1

4.2×8.8+2.2×1.2

=4.2×（2.2×4）+2.2×1.2

=（4.2×4）×2.2+1.2×2.2

=16.8×2.2+1.2×2.2

=2.2×（16.8+1.2）

=2.2×18

=18×（2+0.2）

=18×2+18×0.2

=36+3.6

=39.6

Answer 2

解:可以将8.8运用乘法分配律化为4x2.2同4.2连乘，然后提取2.2，按四则运算法则进行计算。计算过程
4.2ⅹ8.8+2.2ⅹ1.2
=4.2ⅹ4x2.2+2.2x1.2
=2.2ⅹ(16.8+1.2)
=2.2ⅹ18
=39.6。