## Question

###### The manager of retail store is interested to know whether his. customers are making relatively large purchases. He has randomly sampled 25 customers the past , from months, and found that the average sales total for these receiptsis 572.17,with standard deviation of $12.06. Assuming that the sales totals from all customers over the past months are normally distributed, 95% confidence interval for the average sales total for all of his customers from the past months is (567.19,577.151. Based on t

The manager of retail store is interested to know whether his. customers are making relatively large purchases. He has randomly sampled 25 customers the past , from months, and found that the average sales total for these receiptsis 572.17,with standard deviation of $12.06. Assuming that the sales totals from all customers over the past months are normally distributed, 95% confidence interval for the average sales total for all of his customers from the past months is (567.19,577.151. Based on the given interval, can we conclude ata 5% significance level that the average sales total for allof his customers from the past - months is different from $80? Yes, since the entire Interval was below $80 , No; slncethe valuc 580 falls outside of J confidence Interval No,sincethe value 572.17 falls Inside the confidence interval Yes, since thc average from his samplee was differenttrom $80