T h e d ir e c t o r o f g r a d u a t e a d m is s io n s a t a la rg e u n iv e r s ity is a n a ly z in g th e re la tio n s h ip b e tw e e n scores o n t h e m a th p o r t io n o f t h e G r a d u a t e R e c o rd E x a m in a t io n (G R E) a n d s u b s e q u e n t p e rfo rm a n c e in g ra d u a te sch ool, as m e a s u re d b y a s tu d e n t's g ra d e p o in t a v e ra g e (GPA). S h e uses a s a m p le o f 8 s tu d e n ts w h o g r a d u a te d w ith in t h e p a s t fiv e years. T h e d a ta a re as fo llo w s :

GRE 700 720 650 750 680 730 740 780 GPA 3.0 3.5 3.2 3.7 3.1 3.9 3.3 3.5

a. C onstruct a scatterplot placing "GRE" on th e ho rizontal axis.

b. Find th e sam p le regression e q u a tio n for th e m o d el:

GPA = β0 + β1 GRE + ε .

c. W h a t is a student's p re d ic te d GPA if h e /s h e scored 7 1 0 o n th e m a th p o rtio n o f th e GRE?