In a study entitled How Undergraduate Students Use Credit Cards, it was reported that undergraduate students have a mean credit card balance of $3,173 (Sallie Mae, April 2009). This figure was an all-time high and had increased 44% over the previous five years. Assume that a current study is being conducted to determine if it can be concluded that the mean credit card balance for undergraduate students has continued to increase compared to the April 2009 report. Based on previous studies, use a population standard deviation σ = $1,000.
a. State the null and alternative hypotheses.
b. What is the p-value for a sample of 180 undergraduate students with a sample mean credit card balance of $3,325?
c. Using a .05 level of significance, what is your conclusion?