Question

0.18×2.5+0.81×2.5+0.25过程？

Answer 1

解：
原式
=0.18x2.5+0.81x2.5+0.1x2.5
=(0.18+0.81+0.1)x2.5
=1.09x2.5
=2.725

Answer 2

=0.18X2.5十0.81×2.5十0.01X2.5
=2.5×（0.18+0.81+0.01）
=2.5×1=2.5

Answer 3

Answer 4

解：

    0.18×2.5+0.81×2.5+0.25

= 0.45 + 2.025 + 0.25            先乘除后加减

= 2.025 + 0.45 + 0.25            加法交换律，简化运算

= 2.025 + 0.70

= 2.725

或：

    0.18×2.5+0.81×2.5+0.25

= (0.18 + 0.81) × 2.5 + 0.25     合并同类项

= 0.99  × 2.5 + 0.25                 先括号

= (1 - 0.01)  × 2.5 + 0.25          简化运算

= 2.5 - 0.01  × 2.5 + 0.25          拆括号

= 2.5 - 0.025 + 0.25                  先乘除

= 2.5 + 0.25 - 0.025                  加法交换律，简化运算

= 2.75 - 0.025

= 2.725

再或：

    0.18×2.5+0.81×2.5+0.25

= 0.18×2.5+0.81×2.5+0.1×2.5    人为制造同类项   

= (0.18 + 0.81 + 0.1) × 2.5          合并同类项

= 1.09 × 2.5 

= (1.1 - 0.01) × 2.5                     人为制造括号，简化运算

= 2.75 - 0.025                            先括号

= 2.725