In a random sample of 305 Ohio State University female students, 128 responded that, if they had a cell phone, they would be willing to walk somewhere after dark that they would normally not go. Use the above survey results to test the claim that less than half of all Ohio State female students who, if they had a cell phone, would be willing to walk somewhere after dark that they would normally not go. What is the value of the test statistic for this hypothesis test? (Use 2 decimal places in your answer).