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High school mathematics compulsory 3 probability questions! Help me.
(1) The probability of touching the red ball for the first time and the fourth time is the same.

(2) The probability of touching the red ball for the first time is110.

The probability of touching the red ball for the fourth time is. . It seems to be calculated like this:

First of all. Two. The product of the probability of having to take the white ball three times and the probability of having to take the red ball the fourth time; Divide by the probability of getting the white ball for the fourth time.

In short, it is relative to110.

Much worse. . Very, very small probability