please teach to how calculate the mean of several numbers.

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Welcome to our lesson on calculating the mean of several numbers. The mean, also called the average, is a measure of central tendency that represents the typical value in a dataset. To calculate the mean, we use a simple formula: add up all the values, then divide by the number of values. Let's look at an example with the numbers 4, 7, 13, and 16. First, we add these numbers: 4 plus 7 plus 13 plus 16 equals 40. Next, we count how many numbers we have, which is 4. Finally, we divide the sum by the count: 40 divided by 4 equals 10. So the mean of these four numbers is 10. Let's work through another example step by step. We'll calculate the mean of the numbers 5, 8, 12, 15, and 20. Step 1: Add all the numbers together. 5 plus 8 plus 12 plus 15 plus 20 equals 60. Step 2: Count how many numbers we have. There are 5 numbers in our dataset. Step 3: Divide the sum by the count. 60 divided by 5 equals 12. Therefore, the mean of these five numbers is 12. This is the typical value that represents our dataset. Let's visualize what the mean represents. Imagine placing our data points on a number line. Here we have the values 2, 3, 7, 8, and 10. The mean of these numbers is 6. We can think of the mean as the balance point of the dataset. If we were to place weights at each data point on a physical number line, the line would balance perfectly at the mean value. This is why the mean is sometimes called the center of gravity of the data. Notice that the mean doesn't have to be one of the actual data points - it represents the typical value, but might not be a value that actually appears in our dataset. An important characteristic of the mean is that it's sensitive to outliers. Let's see what happens when we introduce an extreme value to our dataset. Here we have a set of numbers: 5, 6, 7, 8, and 9. The mean of these values is 7. Now, let's replace the last value with an outlier. Instead of 9, we'll use 50. Our new dataset is 5, 6, 7, 8, and 50. The mean jumps dramatically to 15.2. Notice how a single extreme value has pulled the mean significantly toward it. This is why the mean might not always be the best measure of central tendency when dealing with data that contains outliers. In such cases, other measures like the median might be more appropriate. Let's summarize what we've learned about calculating the mean. The mean is calculated by adding all values in a dataset and dividing by the count of values. The formula is: Mean equals the sum of all values divided by the number of values. The mean represents the balance point or center of gravity of the data. It's important to remember that the mean is sensitive to outliers, which can pull it toward extreme values. Despite this limitation, the mean is widely used in statistics, science, economics, and everyday life because it takes into account every value in the dataset. When calculating the mean, always remember the three simple steps: sum the values, count the values, and divide the sum by the count.