A report on employment claims that the monthly salary of fresh graduates in the field of Information Systems has a mean of $ 16540.
To investigate this, the university sent 300 questionnaires for 300 randomly chosen graduates. 100 people replied and upon analysis of the 100 data, it was found to have a mean (¯x) of $ 16 080 and a standard deviation (s) of $ 900.
Determine whether the claim of the report is justified by: (a) Constructing a 95% confidence interval, using a critical value of 1.96 and (b) Doing a hypothesis test at the 5% significance level using a critical value of 1.645.