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Three Classical Probability Required in Senior High School Mathematics
1,

The first two digits are 8:

The probability that the first number is 8 is 1/9, and the probability that the second number is 8 is110.

The last six digits are randomly arranged.

So the probability of the first question is1/9 *110 =1/90.

2,

The opposite of the problem is that both numbers are greater than 8.

This probability is

Both digits are 9.

P= 1/90

So the initial probability is 89/90,

3. The probability that the first place is 1 is 1/9.

The probability that the second place is also 1 is110.

The same is P= 1/90.

There are nine groups of such numbers.

So the same probability is110.

P (different) =9/ 10