问题
解答题
| 简便方法计算． 3
（7.25×40%+2.75×
[1.9+19%×（4.8-3
|
答案
（1）3
| 1 |
| 2 |
=3.5×
| 1 |
| 4 |
=3.5×0.25+360×0.25+0.25×36.5
=（3.5+36.5+360）×0.25
=400×0.25
=100；
（2）（7.25×40%+2.75×
| 2 |
| 5 |
=（7.25×40%+2.75×40%）÷20%
=（7.25+2.75）×40%÷20%
=10×40%÷20%
=4÷20%
=20；
（3）[1.9+19%×（4.8-3
| 4 |
| 5 |
| 9 |
| 10 |
=[1.9+0.19×（4.8-3.8）]÷（2.9-1.9）
=（1.9+0.19×1）÷1
=（1.9+0.19）÷1
=2.09÷1
=2.09．
