Rangersteve4x4:

1. Given the linear correlation coefficient r and the sample size n, determine the P-value and use your finding to state whether or not the given r represents a significant linear correlation. r = 0.568, n = 30
a. P-value = 0.0498; significant linear correlation
b. P-value = 0.1387; no significant linear correlation
c. P-value = 0.2987; no significant linear correlation
d. P-value = 0.0011; significant linear correlation

2. The paired data below consist of temperatures on randomly choosen days and how much a certain kind of plant grew in millimeters. Find the value of the linear correlation coefficient r.
Temp - 63, 77, 51, 52, 70, 47, 52, 45, 80
Growth - 38, 41, 52, 15, 34, 35, 17, 8, 16
a. .197
b. .208
c. .164
d. .092

3. Find the coefficient of determination, given that the value of the linear correlation coefficient, r, is -0.673.
a. 0.453
b. 0.346
c. 0.339
d. 0.880

4. An anti-smoking group used data in the table below to relate the carbon monoxide of various brands of cigarettes to their tar and nicotine content. Identify R2, adjusted R2, and the P-value.

CO Tar NIC
15 1.3 17
15 1.3 16
18 1 17
6 0.9 9
5 0.2 4
8 0.9 8
11 0.9 11
17 1.1 16
16 1.3 16
12 0.8 8
19 1.5 19
16 1.1 15
11 0.9 11
9 0.6 7
19 1.2 17

a. 0.972, 0.936, 0.000
b. 0.931, 0.902, 0.000
c. 0.861, 0.900, 0.015
d. 0.888, 0.870, 0.000

5. A set of data consists of the number of hours that high school algebra students spent working with math tutoring software and the grades that they received on a standardized math test. The following regression equation is obtained: y = 41.8 + 11.5x, where x represents the number of hours spent working with the math tutoring software and y represents the grade on the test.
Identify the predictor and response variables.