Sammy wants to know what percent of students at her high school have a driver’s license. She surveys all students in her statistics class and finds that 68% of the students in her sample have a driver’s license. What type of sample did Sammy obtain?
Explain why this sampling method is biased. Is 68% likely to be greater than or less than the percent of all students at her high school who have a driver’s license?
Explain how Sammy could avoid the bias described in part (b).