Question: Refer to the freezer data’s 80
Refer to the freezer data’s 80 individual temperature observations in problem 17.52.
Problem 17.52:
Refer to the freezer problem 17.51 with μ = 23 and σ = 2. Temperature measurements are recorded four times a day (at midnight, 0600, 1200, and 1800). Twenty samples of four observations are shown below.
Problem 17.51:
The temperature control unit on a commercial freezer in a 24-hour grocery store is set to maintain a mean temperature of 23 degrees Fahrenheit. The temperature varies because people are constantly opening the freezer door to remove items, but the thermostat is capable of maintaining temperature with a standard deviation of 2 degrees Fahrenheit. The desired range
is 18 to 30 degrees Fahrenheit.
(a). Prepare a histogram and/or normal probability plot for the sample.
(b). Does the sample support the view that freezer temperature is a normally distributed random variable?
(c). Are the sample mean and standard deviation about where they are expected to be?
Transcribed Image Text:
Sample Midnight At 0600 At 1200 At 1800 Mean 1 25 26 23 23 24.25 2 22 23 28 22 23.75 3 20 24 25 21 22.50 4 21 25 22 23 22.75 5 21 23 21 23 22.00 26 25 27 26 26.00 7 21 23 25 20 22.25 8 25 23 22 25 23.75 9. 22 24 24 22 23.00 10 27 23 26 25 25.25 11 24 23 20 21 22.00 12 25 21 23 20 22.25 13 26 21 21 23 22.75 14 26 22 26 22 24.00 15 21 24 20 19 21.00 16 23 26 23 23 23.75 17 23 21 24 21 22.25 18 25 22 22 23 23.00 21.75 19 24 20 21 22 20 24 21 23 21 22.25
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