A survey was taken of students in math classes to find out how many hours per day students spend on social media. The survey results for the first-, second-, and third-period classes are as follows:

First period: 2, 4, 3, 1, 0, 2, 1, 3, 1, 4, 9, 2, 4, 3, 0

Second period: 3, 2, 3, 1, 3, 4, 2, 4, 3, 1, 0, 2, 3, 1, 2

Third period: 4, 5, 3, 4, 2, 3, 4, 1, 8, 2, 3, 1, 0, 2, 1, 3

Which is the best measure of center for first period and why?

Mean, because there are no outliers that affect the center

Median, because there is 1 outlier that affects the center

Interquartile range, because there is 1 outlier that affects the center**

Standard deviation, because there are no outliers that affect the center

What is the outlier?

There is no outlier. I added one and the interquartile changed.

I'm so sorry, I made a mistake in the question!! It is the best measure of center for second period!! Shall I repost?

To identify the best measure of center for the first-period math class, we need to evaluate the characteristics of each measure: mean, median, interquartile range, and standard deviation.

1. Mean: The mean is the average of a set of values. It is calculated by summing all the values and dividing by the total number of observations. This measure is influenced by extreme values or outliers. However, if there are no outliers that significantly affect the overall distribution, the mean can be a suitable measure of center.

2. Median: The median represents the middle value when the data is ordered from smallest to largest. It is unaffected by extreme values or outliers. If there is an outlier affecting the center, the median can provide a more representative measure.

3. Interquartile Range (IQR): The IQR measures the spread of the central half of the data, specifically the range between the lower quartile (the 25th percentile) and the upper quartile (the 75th percentile). While the IQR does not directly represent the center, it can indicate the spread of the central data better in the presence of outliers.

4. Standard Deviation: The standard deviation measures the average amount by which values in a dataset differ from the mean. Like the mean, it can be influenced by outliers. However, if there are no outliers that significantly impact the distribution, the standard deviation can be used to understand the variability of the data.

Based on the given options, the best measure of center for the first-period math class is the median. Since there is one outlier in the first-period data that affects the center, the median would provide a more accurate representation of the central tendency as it is not impacted by outliers.