Final answer:
The ideal frequency of IT audits typically is on an annual basis, yielding about 20 audits over 20 years. Without context, calculating the probability of avoiding audits or being audited multiple times is not possible.
Step-by-step explanation:
The ideal frequency of IT audits in an organization depends on various factors, including the size of the organization, the complexity and criticality of its IT environment, regulatory requirements, and the organization's risk profile. However, as a rule of thumb, many businesses aim for an annual IT audit. In a 20-year period, one would expect to have around 20 audits if they are conducted annually.
The probability of not being audited at all depends on the audit frequency and other specific factors such as the audit selection process and organizational policies. It's challenging to calculate this without additional context. Similarly, to determine the probability that a person is audited more than twice, specifics about the frequency of audits and the selection criteria are needed.