简便计算!1.2.5×9.8 2.1.25×25×3.23.2.4-1.375+5分之3 4.3分之1÷7分之3×14分之5
来源：学生作业帮助网 编辑：六六作业网 时间：2024/04/28 12:57:45
简便计算!1.2.5×9.82.1.25×25×3.23.2.4-1.375+5分之34.3分之1÷7分之3×14分之5简便计算!1.2.5×9.82.1.25×25×3.23.2.4-1.375+5
简便计算!1.2.5×9.8 2.1.25×25×3.23.2.4-1.375+5分之3 4.3分之1÷7分之3×14分之5
简便计算!1.2.5×9.8 2.1.25×25×3.2
3.2.4-1.375+5分之3 4.3分之1÷7分之3×14分之5
简便计算!1.2.5×9.8 2.1.25×25×3.23.2.4-1.375+5分之3 4.3分之1÷7分之3×14分之5
1.2.5×9.8
=2.5x(10-0.2)
=2.5x10-2.5x0.2
=25-0.5
=24.5
2.1.25×25×3.2
=(1.25x8)x(0.4x25)
=10x10
=100
3.2.4-1.375+5分之3
=2.4-+0.6-1.375
=3-1.375
=1.625
4 3分之1÷7分之3×14分之5
=1/3x7/3x5/14
=5/18
2.5×9.8
=2.5x(10-0.2)
=2.5x10-2.5x0.2
=25-0.5
=24.5
1.25×25×3.2
=(1.25x8)x(25x0.4)
=10x10=100
2.4-1.375+5分之3
=2.4-5分之3-1又8分之1
=2-1又8分之1=7/8
3分之1÷7分之3×14分之5
=1/3x7/3x14分之5
=1/3（7/3x5/14)
=1/3x5/6
=5/18
第一道把九点八拆成4×2.45，再把4和2.5相乘。
第二道把3.2拆成4×0.8，再把4和25相乘，0.8和1.25相乘。