Please refer to the results in the table and briefly comment the difference in age between the two groups (patients and control).

Answer Each of the two samples (patients and control individuals) consists of 133 individuals. The average age in both samples is 67.6 years old. A t-test is used to test wethere there is any significant difference in the average age between the two underlying populations (from which the two samples are drawn). The Null hypothesis that the average age is the same in the two populations (i.e. their difference is equal to zero) is tested against the Alternative Hypothesis that it is not (i.e. the difference is not equal to zero). According to the p-value reported in the table (=1), the Null Hypothesis is not rejected at any significance level. Thus, based on the observed sample information, no significant difference exist in the average age of the population of patients waiting for total hip or knee replacement and the general population.