The standard deviation of 7 scores 1, 2, 3, 4, 5, 6, 7 is

• A: 4
• B: 2
• C: 2.6457513110645906
• D: 3

To find the standard deviation of the scores 1, 2, 3, 4, 5, 6, and 7, we first need to calculate the mean (average) of these numbers.

Step 1: Calculate the Mean

The mean is calculated by adding all the scores together and dividing by the number of scores.

• Sum of scores: 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28
• Number of scores: 7
• Mean = 28 / 7 = 4

Step 2: Calculate the Variance

Next, we find the variance by calculating the average of the squared differences from the mean.

• Differences from the mean: (1-4), (2-4), (3-4), (4-4), (5-4), (6-4), (7-4)
• Squared differences: 9, 4, 1, 0, 1, 4, 9
• Sum of squared differences: 9 + 4 + 1 + 0 + 1 + 4 + 9 = 28
• Variance = 28 / 7 = 4

Step 3: Calculate the Standard Deviation

The standard deviation is the square root of the variance.

• Standard Deviation = √4 = 2

Thus, the standard deviation of the scores is 2. Therefore, the correct answer is B: 2.