欧阳修在《卖油翁》中写道:“(翁)乃取一葫芦置于地,以钱覆其扣,徐以杓酌油沥之,自钱孔入,而钱不湿.因曰:‘我亦无他,唯手熟尔.’”可见技能都能透过反复苦练而达至熟能生巧之境的.若铜钱是直径为4cm的圆,中间有边长为1cm的正方形孔,你随机向铜钱上滴一滴油,则油(油滴的大小忽略不计)正好落入孔中的概率为( )
![](https://img.xkw.com/dksih/QBM/2019/5/31/2215419858845696/2217159574183936/STEM/b70355056dd64d7ea94edf97f5f56d1c.png?resizew=116)
![](https://img.xkw.com/dksih/QBM/2019/5/31/2215419858845696/2217159574183936/STEM/b70355056dd64d7ea94edf97f5f56d1c.png?resizew=116)
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更新时间:2019-05-23 08:45:38
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