Which value on the number line is the best estimate of the center of the data set?



A line plot with twenty-two data values. Labels are at zero, three, six, nine, and twelve. Tick marks are every one unit. Values appear as x marks above the line. Plot data values are one x mark above one, one x mark above two, two x marks above three, two x marks above four, three x marks above five, four x marks above six, three x marks above seven, three x marks above eight, two x marks above nine, and one x mark above eleven.