A gasoline distributor wonders whether an individual's income levels influences the grade of gasoline purchased. Using $\alpha$ = .01, the critical chi-square value is ___.
A)15.09
B)7.88
C)9.21
D)16.81
E)17.89

Question

A gasoline distributor wonders whether an individual's income levels influences the grade of gasoline purchased.  Using $\alpha$ = .01, the critical chi-square value is ___.
A)15.09 
B)7.88 
C)9.21 
D)16.81 
E)17.89

Quizplus · Accepted Answer

Based on the information given, we are conducting a chi-square goodness-of-fit test with one variable (income levels) and multiple categories (gasoline grades). The degrees of freedom for this test are equal to the number of categories minus one, which in this case is three (there are four possible gasoline grades). With an alpha level of .01 and three degrees of freedom, the critical chi-square value is 9.21, so the answer is C.

A Gasoline Distributor Wonders Whether an Individual's Income Levels Influences α\alphaα

A Gasoline Distributor Wonders Whether an Individual's Income Levels Influences $\alpha$