Hypothesis testing

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?

No, that’s not necessary. Since it was a random sample of 40 customers, we cannot make conclusions about the whole data using that sample.

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