Final answer:
To calculate the standard deviation, find the variance of the data set by finding the average of the squared deviations from the mean. Then, take the square root of the variance. For this data set, the standard deviation is approximately 1.87.
Step-by-step explanation:
To calculate the standard deviation, we first need to find the variance. The variance is the average of the squared deviations of each data point from the mean. Let's calculate the variance step-by-step:
- Find the deviation of each data point from the mean:
2 - 4 = -2
3 - 4 = -1
4 - 4 = 0
4 - 4 = 0
7 - 4 = 3 - Square each deviation:
(-2)^2 = 4
(-1)^2 = 1
0^2 = 0
0^2 = 0
3^2 = 9 - Sum up all the squared deviations:
4 + 1 + 0 + 0 + 9 = 14 - Divide the sum by n-1, where n is the number of data points:
14 / (5-1) = 14 / 4 = 3.5
Next, we find the square root of the variance to get the standard deviation:
sqrt(3.5) ≈ 1.87
So, the standard deviation for this data set is approximately 1.87.