Virtual call centers are staffed by individuals working out of their homes. Most home agents earn $10 to $15 per hour without benefits versus $7 to $9 per hour with benefits at a traditional call center (BusinessWeek,January 23, 2006). Regional Airways is considering employing home agents, but only if a level of customer satisfaction greater than 80%can be maintained. A test was conducted with home service agents. In a sample of 300 customers, 252 reported that they were satisfied with service.
a) What is your point estimate of the percentage of satisfied customers?
b) What is the p-value provided by the sample data? (This is the part I don't understand, there is no standard deviation given, so I don't know how to complete either formula (t or z score))