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) III only
B) I only
C) II and III only
D) I, II, and III
E) II only

Question

Quizplus · Accepted Answer

A correlation of r = 0.30 indicates a positive relationship, 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