Which pair commonly shows a positive correlation?

• A. Temperature and distance
• B. Height and weight
• C. Age and IQ
• D. Shoe size and GPA

Answer: (B)

A positive correlation means that as one variable increases, the other tends to increase as well. Height and weight fit this pattern because, in general, taller people tend to weigh more; body size tends to scale up together, producing an upward, roughly linear relationship in many groups.

Temperature and distance don’t have a consistent, inherent link—how far someone travels isn’t reliably tied to the temperature. Age and IQ don’t show a steady positive relationship across a wide age range, since IQ is relatively stable in adulthood and development effects stabilize after childhood. Shoe size and GPA are unrelated in a systematic way—foot size doesn’t predict academic performance.

So height and weight best illustrate the idea: as one grows taller, weight tends to rise as well, reflecting a positive correlation.