3.9+3.99+3.999+3.9999简便计算

3.9+3.99+3.999+3.9999简便计算
2025-03-22 00:20:05
推荐回答(3个)
回答1:

3.9+3.99+3.999+3.9999

=4×4-0.1-0.01-0.001-0.0001
=16-0.1111
=15.8889

回答2:

3.9+3.99+3.999+3.9999
=4-0.1+4-0.01+4-0.001+4-0.0001
=(4+4+4+4)-(0.1+0.01+0.001+0.0001)
=16-0.1111
=15.8889

回答3:

4-0.1+4-0.01+4-0.001+4-0.0001=12-0.1111=11.8889