D. City officials are interested in knowing whether there is an association between the air quality and the
percent cloudiness on a given day. For each quality reading above, the respective percent of cloudiness
is 25, 50, 30, 80, 90, 100, 70, and 40.
i.
If the average cloudiness for this sample is 60.625 with a standard deviation of 28.3395, which variable
is more dispersed, air quality of cloudiness? Use coefficient of variation.
ii.
Calculate the covariance and the correlation coefficients. Use a table to show your calculations.
iii.
What is the association between air quality and cloudiness?