If the first digit of a seven-digit telephone number cannot be a 0 or 1, what is the probability that a number chosen at random will have all seven digits the same?

Question

If the first digit of a seven-digit telephone number cannot be a 0 or 1, what is the probability that a number chosen at random will have all seven digits the same? ​

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The Answer of If the first digit of a seven-digit telephone number cannot be a 0 or 1, what is the probability that a number chosen at random will have all seven digits the same? ​

If the First Digit of a Seven-Digit Telephone Number Cannot