University of Phoenix Material

PROBABILITY

Maximum and Minimum Temperatures

Search the Internet for U.S. climate data.

Choose the city in which you live.

Click on the tab that reads “Daily.”

1. Prepare a spreadsheet with three columns: Date, High Temperature, and Low Temperature. List the past 60 days for which data is available.

2. Prepare a histogram for the data on high temperatures and comment on the shape of the distribution as observed from these graphs.

3. Calculate  and S. mean 40.7483

Standard deviation 1.905878

4. What percentage of the high temperatures are within the interval  – S to  + S? 38.842452 to 42.654208 48/60=.8 or 80%

5. What percentage of the high temperatures are within the interval  – 2S to  + 2S? 37.111595 to 44.38070 56/60=.9333 or 93.33%

6. How do these percentages compare to the corresponding percentages for a normal distribution (68.26% and 95.44%, respectively)? The percentages are higher and lower than those of nirmal distrbution

7. Repeat Parts 2 to 6 for the minimum temperatures on your spreadsheet.

24.883551 to 31.026449
59/60= 0.9833 or 98.33%
18.41383 to 37.46617
59/60= 0.9833 or 98.33%

8. Would you conclude that the two distributions are normally distributed? Why or why not?

two distributions are not normally distributed because the points do not form a bell shaped curve. Both graphs start high and taper off towards the higher temperatures. Neither of the curves follow the 68% to 95% rule to be considered normally distributed.