Question

A researcher has collected the following sample data. The mean of the sample is 7 .

6 8 15 3 3
The variance is a. 19.6 b. 80 c. 24.5 d. 4.950

Answer 1

To calculate the variance of a sample, subtract each value from the mean, square the result, find the average of the squared differences.

Step-by-step explanation:

To calculate the variance of a sample, you first need to calculate the mean of the sample. In this case, the mean of the sample is 7. Next, subtract each value from the mean and square the result. Then, find the average of the squared differences. The variance is the average squared difference.

Using the given sample data: 6, 8, 15, 3, 3, calculate the variance as follows:

1. Subtract the mean (7) from each value: -1, 1, 8, -4, -4
2. Square each difference: 1, 1, 64, 16, 16
3. Find the average of the squared differences: (1 + 1 + 64 + 16 + 16) / 5 = 19.6

Therefore, the variance of the sample is 19.6.