Dishonest people try to fake numbers in tax returns, invoices, or expense account laims. It's actually hard to make up numbers that are fully realistic. One reason is that the first digits of numbers in legitimate records often follow a model known as Benford's Law. Call the first digit of a randomly chosen record X for short. Benford's Law gives this probability model for X: First digit X 1 2 3 4 5 6 7 8 9 probability 0.301 0.176 0.125 0.097 0.079 0.067 0.058 0.051 0.046 For instance - if ABC company has been keeping legitimate records of its accounts, the probability that a randomly chosen record starts with the number 7 is 0.058. A company without this probability has been jiggering its records somehow. Reference: Benford's law If Tembo Safaris keeps legitimate records, what percent of those records will start with the digits 5, 6 or 7?