Reference no: EM131749414

Question: Control limits for air conditioner thermostats. A maker of auto air conditioners checks a sample of 5 thermostatic controls from each hour's production. The thermostats are set at 72°F and then placed in a chamber where the temperature is raised gradually. The temperature at which the thermostat turns on the air conditioner is recorded. The process mean should be μ = 72°. Past experience indicates that the response temperature of properly adjusted thermostats varies with σ = 0.4°F.

(a) The mean response temperature x¯ for each hour's sample is plotted on an x¯ control chart. Calculate the center line and control limits for this chart.

(b) The sample standard deviation s for each hour's sample is plotted on an s control chart. What are the center line and control limits for this chart?