Century National Bank case A

Recent years have also seen an increase in the use of

ATM machines. When Mr. Selig took over the bank, the

mean number of transactions per month per customer was

8; now he believes it has increased to more than 10. In fact,

the advertising agency that prepares TV commercials for

Century would like to use this on the new commercial being

designed. Is there sufficient evidence to conclude that

the mean number of transactions per customer is more than

10 per month? Could the advertising agency say the mean

is more than 9 per month?