The table below shows how many minutes Mary spent exercising each day for the last two weeks.
Mary's Time Spent Exercising
Sun Mon Tue Wed Thu Fri Sat
Week 1 0 min 45 min 45 min 40 min 50 min 35 min 0 min
Week 2 0 min 45 min 50 min 45 min 40 min 50 min 35 min
Which of the following best explains why the mean is NOT an appropriate indicator of how much time Mary spends exercising on a typical day?
A.
There is more than one mean.
B.
The mean is not an integer value.
C.
The mean is skewed by the days Mary did not exercise.
D.
The set of data points is too small.
C. The mean is skewed by the days Mary did not exercise.
dumbooo
be quiet bozo @no
To determine why the mean may not be an appropriate indicator of how much time Mary spends exercising on a typical day, we need to analyze the given options.
Option A states that there is more than one mean. However, the mean is a single value that represents the average of a set of data, so this option is incorrect.
Option B suggests that the mean is not an integer value. However, the mean can be a decimal or fraction, so this option is also incorrect.
Option C states that the mean is skewed by the days Mary did not exercise. This implies that the days on which Mary did not exercise significantly affect the mean. To determine the accuracy of this statement, let's calculate the mean for both weeks separately.
For Week 1:
Total time spent exercising = 0 + 45 + 45 + 40 + 50 + 35 + 0 = 215 minutes
Mean = Total time spent exercising / Number of days = 215 / 7 = 30.71 minutes per day
For Week 2:
Total time spent exercising = 0 + 45 + 50 + 45 + 40 + 50 + 35 = 265 minutes
Mean = Total time spent exercising / Number of days = 265 / 7 = 37.86 minutes per day
As we can see, the mean for Week 1 is 30.71 minutes per day, while the mean for Week 2 is 37.86 minutes per day. This demonstrates that the mean is indeed influenced by the days Mary did not exercise, as it gives more weight to the days she did exercise.
Therefore, option C is correct. The mean is not an appropriate indicator of how much time Mary spends exercising on a typical day because it is skewed by the days she did not exercise.
Option D suggests that the set of data points is too small. While a larger dataset can yield more accurate results, the given data is sufficient for calculating the mean. Hence, option D is incorrect.