What is the average total Trihalomethanes (TTHM) given the following data: Monday - 0.0073 mg/L, Tuesday - 0.0085 mg/L, Wednesday - 0.0094 mg/L, Thursday - 0.0079 mg/L, Friday - 0.0092 mg/L?

To find the average Total Trihalomethanes (TTHM) concentration from the provided data, one must sum all the daily measurements and then divide by the number of days.

Adding the values together gives:

0.0073 mg/L (Monday) + 0.0085 mg/L (Tuesday) + 0.0094 mg/L (Wednesday) + 0.0079 mg/L (Thursday) + 0.0092 mg/L (Friday) = 0.0423 mg/L

Now, since there are 5 days in total, you would divide the sum by 5 to determine the average:

0.0423 mg/L ÷ 5 = 0.00846 mg/L

When rounded to four significant figures, this average rounds to 0.0085 mg/L. Thus, selecting 0.0085 mg/L as the answer accurately reflects the correct average concentration of TTHMs derived from the data provided.

This is important as the average TTHM level is a critical metric for water quality and can impact regulatory compliance and public health. Each other option does not accurately reflect the calculated average based on the provided figures.