Question

The table below lists the scores of nine students in Chemistry and Physics. student 1/2/3 4 5 6 7 8 chemistry 3/6/5/8 a 4 5 7 18 Physics 657 612 314 6 1 9. Find the correlation of the variables and x and y b. Compute for b and m in the linear regression c. Give the regression equation d. Predict the Physics score of the students when he or she got a score of 10 in chemistry

Answer 1

Solution:

Considering x as the Chemistry score and y as the Physics score.

Chemistry x Physics y 64 I Σv = 255 Ι Σ = 369 | Σν' = 227 Σx= 55 X = 6.111 Σv= 43 y = 4.778 Ι ηΣ» –ΣΣν 9x255-55x43 [9x369-55 ][9» 227-43] -70 2390 6331 -0.2921 ηΣχν-ΣΣν _9x255-55x43 Σ-Σκαι, 19x369-55 -0.23649 Intercept, b=y- = 4.778-(-0.23649x6.111) = 6.223

a. The correlation between the variables x and y is

r= -0.2921

b.

b= 6.223, m = -0.23649

c.The regression equation is:

y = 6.223 – 0.23649x

d.The predicted physics score is:

y = 6.223 – 0.23649 X 10

-3,8581