Step 1 :Given the data of time and percent of chlorine remaining, we are asked to find the correlation coefficient between these two variables.
Step 2 :The correlation coefficient, often represented by 'r', is a statistical measure that calculates the strength of the relationship between the relative movements of two variables. The values range between -1.0 and 1.0. A correlation of -1.0 shows a perfect negative correlation, while a correlation of 1.0 shows a perfect positive correlation. A correlation of 0.0 shows no linear relationship between the movement of the two variables.
Step 3 :We can create two lists, one for time and one for percent of chlorine remaining, and then use the correlation coefficient formula to find the correlation coefficient.
Step 4 :Let's denote the time as \( t = [1, 2, 3, 4, 5, 6] \) and the percent of chlorine remaining as \( c = [84.7, 70.7, 65.6, 47.2, 32.2, 20.5] \).
Step 5 :By calculating, we find that the correlation coefficient \( r = -0.992992922715922 \).
Step 6 :Rounding to the nearest thousandth, we get the final answer: The correlation coefficient between time and percent of chlorine remaining is \( r = \boxed{-0.993} \).