Following is a hypothesis testing question i am stuck at can anyone help ?
Records of a Bank indicate that individual customers pay on an average Rs. 155 per year as service charges with standard deviation Rs. 45. A random sample of 40 customer’s bills during a given month produced a sample mean of Rs. 160 as service charges. At 5% significance, can we say that the company’s records indicate lesser mean than the actual i.e. actual mean is more than Rs.155?