Finding The Correlation Between The Number Of Dominoes Average Time

Falling Dominoes In our AP Statistics course, the class was tasked with finding a possible association between the number of dominoes and the time it takes for them to fall. In groups of three or four, dominoes were set up 1 inch apart with a meter stick. Next, they were knocked over while the amount of time in seconds for all of the dominoes to fall was recorded with a stopwatch for trials of 10 dominoes through 100 dominoes. While discussing the procedure, the group assumed that as the number of dominoes increased so would the amount of seconds it takes for the dominoes to fall to the ground. The data recorded for the group is represented in figure 1 below. Number of Dominoes Average Time (in sec) Number of Dominoes Average Time (in sec) Number of Dominoes Average Time
For this association, the correlation coefficient of 0.9783 indicates that there is a positive strong linear relationship between time in seconds and number of dominoes, meaning as time increases so does the number of dominoes. The slope of the regression line is positive, so, as assumed, as the number of dominoes increases the time in seconds for them to fall also increases. Accordingly, the slope, b, is positive and equals 0.025. The regression line predicts that the time in seconds for the dominoes to fall increases by 0.025 for every increase of 1 unit in the number of dominoes. As for the y-intercept, a, the regression line predicts