Steve Cutter sells Big Blade lawn mowers in his hardware store, and he is interested in comparing
the reliability of the mowers he sells with the reliability of Big Blade mowers sold nationwide. Steve
knows that only 15 percent of all Big Blade mowers sold nationwide requires repairs during the first
year of ownership. A sample of 120 of Steve’s customers revealed that exactly 22 of them required
mower repairs in the first year of ownership. At a 0.02 level of significance, is there evidence that
Steve’s Big Blade mowers differ in reliability from those sold nationwide?
2 answers