(Solved):   A random sample of 18 Australian fruit and vegetable farmers is selected and surveyed. The ...

 

A random sample of 18 Australian fruit and vegetable farmers is selected and surveyed. These farmers all supply large Australian supermarkets. One survey question asks farmers to indicate how many years they have been supplying their fresh produce to these supermarkets. From this sample, the average number of years is calculated to be \( 9.2 \) years. This particular survey has been ongoing for many years. Based on historical data, it is believed that the standard deviation for all fruit and vegetable farmers in Australia supplying large supermarkets is \( 2.5 \) years. Using this information, construct a \( 95 \% \) confidence interval for the population mean number of years that Australian fruit and vegetable farmers have been supplying their produce to the large Australian supermarkets.