用简便方法计算:19.88+9.9+198.8

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/23 16:55:06
用简便方法计算:19.88+9.9+198.8用简便方法计算:19.88+9.9+198.8用简便方法计算:19.88+9.9+198.819.88+9.9+198.8=19.88+19.88×10+

用简便方法计算:19.88+9.9+198.8
用简便方法计算:19.88+9.9+198.8

用简便方法计算:19.88+9.9+198.8
19.88+9.9+198.8
=19.88+19.88×10+9.9
=19.88×(1+10)+9.9
=19.88×11+9.9
=19.88×11+0.9×11
=11×(19.88+0.9)
=11×20.78
=(10+1)×20.78
=20.78×10+20.78
=207.8+20.78
=228.58