Find the variance of the following scores on an exam 92,95,85,80,75 by using a table to calculate
In order to calculate the variance, we need to follow these steps:
Step 1: Find the mean of the scores.
Step 2: Subtract the mean from each score, and square the result.
Step 3: Find the sum of the squared differences.
Step 4: Divide the sum by the number of scores minus 1.
Let's go through each step:
Step 1: Find the mean.
Mean = (92 + 95 + 85 + 80 + 75) / 5 = 87.4
Step 2: Subtract the mean and square the result.
(92 - 87.4)^2 = 22.09
(95 - 87.4)^2 = 56.84
(85 - 87.4)^2 = 5.76
(80 - 87.4)^2 = 54.76
(75 - 87.4)^2 = 151.84
Step 3: Find the sum of the squared differences.
22.09 + 56.84 + 5.76 + 54.76 + 151.84 = 291.29
Step 4: Divide the sum by the number of scores minus 1.
Variance = 291.29 / (5 - 1) = 291.29 / 4 = 72.82
Therefore, the variance of the given scores is 72.82.