In order to study the amounts owed to the city, a city clerk takes a random sample of 16 files from a cabinet containing a large number of delinquent accounts and finds the sample average amount owed to the city to be $230 with a sample standard deviation of $36.It has been claimed that the true mean amount owed on accounts of this type is greater than $250.

Assume that the amount owed is a normally distributed random variable.The value of the test statistic for testing the claim therefore is (round your answer to two decimal places):