6.2 When a claim or statement is made about the difference between two population means for the same random variable, the claim can be tested using the sampling distribution of the difference between two sample means. One example is: Is the average age of female shoppers at Truworths lower (i.e. are they younger?) than the average age of female shoppers at Foschini? Explain the kind of information that is required to perform such two-sample hypothesis tests.