According to Moebs Services Inc., the cost of an individual checking account at U.S. community banks to these banks was between $175 and $200 in 2011 (Time, November 21, 2011). Suppose that the average annual cost of individual checking accounts at U.S. community banks to these banks was $190 in 2011. A recent sample of 40 individual checking accounts selected from U.S. community banks showed that they cost these banks an average of $211 per year with a standard deviation of $35.
a. Using α = .025, can you conclude that the current average annual cost of individual checking accounts at U.S. community banks to these banks is higher than $190? Use the critical-value approach.
b. Find the range of the p-value for the test of part a. What is your conclusion with α =.025?