Evaluating Data: Mean, Median, and Range

Understanding the mean, median, and range is essential for analyzing data sets effectively.

• Mean: The average of a set of numbers, calculated by dividing the sum of the numbers by the count of the numbers.

• Median: The middle value of a data set when it is ordered from least to greatest. If there is an even number of values, the median is the average of the two middle numbers.

• Range: The difference between the highest and lowest values in a data set.

Example Problem

Consider the data set: 3, 7, 2, 9, 5.

1. Calculate the Mean:

   • Sum of numbers: $3 + 7 + 2 + 9 + 5 = 26$
   • Count of numbers: $5$
   • Mean: $\frac{26}{5} = 5.2$

2. Calculate the Median:

   • Ordered data set: 2, 3, 5, 7, 9
   • Middle value (3rd number): $5$
   • Median: $5$

3. Calculate the Range:

   • Highest value: $9$
   • Lowest value: $2$
   • Range: $9 - 2 = 7$

Key Questions

• What is the mean of the data set: 10, 20, 30, 40, 50?
• How do you find the median of the numbers: 4, 1, 7, 8?
• If the range of a data set is 15 and the lowest value is 5, what is the highest value?
• Why is it important to understand the median in a skewed data set?

Keywords

• Mean
• Median
• Range
• Data Analysis
• Statistics