Question: According to HowtoAdvice.com, the average price
According to HowtoAdvice.com, the average price charged to a customer to have a 12′ by 18′ wall-to-wall carpet shampoo cleaned is about $50. Suppose that a start-up carpet-cleaning company believes that in the region in which it operates, the average price for this service is higher. To test this hypothesis, the carpet-cleaning company randomly contacts 23 customers who have recently had a 12′ by 18′ wall-to-wall carpet shampoo cleaned and asks the customers how much they were charged for the job. Suppose the resulting data are given below and that the population standard deviation price is $3.49. Use a 10% level of significance to test the hypothesis. Assume that such prices are normally distributed in the population. What is the observed value? What is the p-value? What is the decision? If the null hypothesis is rejected, is the result substantive?
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