Have you made any attempt at all? The first problem is really just simple arithmetic. Show us what you have tried for the second so we will know what kind of help you need.
I am trying to figure this out using a TI-83 calculator.
Based on the data from six students, the regression equation equation relating number of hours of preparation (x) and test score (y) is y=67.3+1.07x. The same data yield r=0.224 and y=75.2. What is the best predicted test score for a student who spent 4 hours preparing for the test?
Given linear correlation coefficient r and the sample size n, determine the critical values of r and use your finding to state whether or not the given r represents a significant linear correlation. Use a significant level of 0.05
r= -.242 n=90
A. Critical Values r=0.217 significant linear correlation
B. Critical Values r= (+ or -) 0.217 no significant linear correlation
C. Critical Values r= (+ or -) 0.207 significant linear correlation
D. Critical Values r- (+ or -) 0.207 no significant linear correlation