Question 8.72

41. A computer assigns three-character log-in IDs that may contain the digits 0 to 9 as well as the letters to , with repeats allowed.

  1. What is the probability that your ID contains no ?
  2. What is the probability that your ID contains no digits?

41.

(a) There are different codes. The probability of no is as follows:

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(b) The probability of no digits is as follows: