Final answer:
The question requires calculating the probability of a sample proportion based on a claimed rate of shipping orders, which cannot be completed without specific data from the auditors' sample. Normally, the calculation depends on statistical methods or simulations. The part B discussion conceptually addresses factors that support the claim's credibility but cannot be definitively answered without audit details.
Step-by-step explanation:
The question focuses on determining the probability of observing a sample proportion of orders shipped within four working days as small as or smaller than that in an auditors' sample, given that Seams Personal claims a 95% success rate. However, the actual proportion from the auditors' sample is not provided, which makes it impossible to perform this computation. Typically, the probability would be computed using the normal approximation to the binomial distribution or a simulation method if the standard deviation and mean of the sampling distribution were known.
For Part B of the question, without the audit results, it's not possible to definitively determine why the probability calculation supports the 95% claim. Generally, if the sample proportion is consistent with the claim, this would lend support to the company's claim. A large sample size and a reliable audit conduct are factors that would increase the trustworthiness of the claim.