Stats WS 10.3

1- The US Navy has done a lot of research on the optimal time for scuba divers to stay submerged at different depths. x = depth of dive (in meters), and y = time (in hours). A random sample of 7 divers showed the sample correlation to be r = -.976

Use a 1% significance level to see if there is a negative correlation.

2- A local car dealership offers a new vehicle with many different options. If x = the number of options and y = price of car, a sample of 5 cars showed that r = .947.

At the 1% level of significance, test to see if there is a positive correlation.

3- A chemistry lab project was to see if copper sulfate dissolved more in higher temperatures of water. If x was the temperature, and y was the weight of the dissolved copper sulfate, a sample of 7 experiments showed that r = .881. At the 5% level of significance test to see if there is correlation between temperature and solubility.