Question

determine whether the graph shows a positive correlation, a negative correlation, or no correlation. if there is a positive or negative correlation, describe its meaning in the situation. sport utility vehicle sales in the u.s., 1991-2001
vehicles (millions) y - axis, year (1990, 1992, 1994, 1996, 1998, 2000, 2002) x - axis
source: the world almanac, 2003

Explanation:

Step1: Analyze the trend of the data points

Looking at the graph of Sport Utility Vehicle Sales in the U.S. from 1991 - 2001, as the year (x - axis) increases, the number of vehicles sold (y - axis) also increases. The data points show an upward - sloping pattern.

Step2: Determine the type of correlation

A positive correlation is when as one variable (in this case, the year) increases, the other variable (number of sport utility vehicle sales) also increases. Since the sales of sport utility vehicles increase as the years from 1991 to 2001 pass, there is a positive correlation.

Step3: Describe the meaning of the positive correlation

The positive correlation means that over the period from 1991 to 2001, as time (measured by the year) went on, the number of sport utility vehicles sold in the U.S. tended to increase. In other words, there was a general trend of increasing sales of sport utility vehicles during this decade.

Answer:

The graph shows a positive correlation. The meaning is that from 1991 to 2001, as the years passed, the number of sport utility vehicles sold in the U.S. generally increased.