题目

Many teenagers feel that the most important people in their lives are their friends. They believe that their family members, especially their parents, don’t know them as well their friends do. In large families, it is often for brothers and sisters to fight with each other and then they can only go to their friends for advice. It is very important for teenagers to have one good friend or many friends. Even when they are not with their friends, they usually spend a lot of time talking among themselves on the phone. This communication is very important in children’s growing up, becau在一个不透明的口袋里装有只有颜色不同的黑、白两种颜色的球共20只,某学习小组做摸球实验,将球搅匀后从中随机摸出一个球记下颜色,再把它放回袋中,不断重复.下表是活动进行中的一组统计数据:摸球的次数n1001502005008001000摸到白球的次数m5896116295484601摸到白球的频率0.580.640.580.590.6050.601(1)请估计:当n很大时,摸到白球的频率将会接近______;(2)假如你去摸一次,你摸到白球的概率是______,摸到黑球的概率是______;(3)试估算口袋中黑、白两种颜色的球各有多少只?(4)解决了上面的问题,小明同学猛然顿悟,过去一个悬而未决的问题有办法了.这个问题是:在一个不透明的口袋里装有若干个白球,在不允许将球倒出来数的情况下,如何估计白球的个数(可以借助其他工具及用品)请你应用统计与概率的思想和方法解决这个问题,写出解决这个问题的主要步骤及估算方法.
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