simple probability curve

例句：

1. 1. Thesimple probability curve shows the distribution of thepopulation.
   简单概率曲线显示了人口的分布情况。
2. 2. The simple probability curve helps usunderstand the relationship between variables.
   简单概率曲线有助于我们理解变量之间的关系。
3. 3. Thesimple probability curve is usedto calculate the expected value ofa random variable.
   简单概率曲线用于计算随机变量的期望值。