The average landscaper mows 1.4 acres of grass per day. Because labor costs are increasing, the city decides to try a new brand of mower. Ten randomly selected landscapers are given the new mowers. After a test period, these 10 landscapers cut an average of 2.1 acres per day, with a standard deviation of .6 acre. If the costs are similar, should the city purchase more new mowers?

1. State Ho and Ha formally and in "English" (e.g. Ho: u = 20 Ha: u <> 20; Ho: The average (variable name) is 20 Ha: The average "variable name" is NOT 20)
2. Show the math
3. Reject or retain the Ho at a = .05; provide the "critical t" value at that level
4. Make all tests and hypotheses two-tail
5. Explain the findings