Manager of a small business is thinking about establishing a new billing system for the customers. After a comprehensive financial analysis, he concludes that the new system would be cost-effective only if the mean value of weekly accounts is greater than $50. A random sample of 46 weekly accounts is drawn for which the sample mean is $52, and sample standard deviation is $10. The manager believes that the accounts are normally distributed. Is there enough evidence at the 5% significance level to conclude that the new system would be cost-effective?

• State the parameter of interest and the null and alternative hypotheses.

• State the standardised test statistic and the sampling distribution of it under the null hypothesis.

• State the level of significance. What does the level of significance measure? Explain

• State the decision rule with the test statistic method