The correlation between a family's weekly income and the amount they spend on restaurant meals
Is found to be $r = 0.30$
Which must be true?
I. Families tend to spend about 30% of their incomes in restaurants.
II. In general, the higher the income, the more the family spends in restaurants.
III. The line of best fit passes through 30% of the (income, restaurant$) data points.
A) II only
B) II and III only
C) I only
D) I, II, and III
E) III only

Question

Quizplus · Accepted Answer

The correlation coefficient $r = 0.30$ indicates a positive relationship between income and spending on restaurant meals, meaning that generally, as income increases, spending on restaurant meals also increases. However, it does not imply that families spend 30% of their income on restaurants or that the line of best fit passes through 30% of the data points.

The Correlation Between a Family's Weekly Income and the Amount r=0.30r = 0.30r=0.30

The Correlation Between a Family's Weekly Income and the Amount $r = 0.30$