Find the variance and 0 of the following scores on an exam: 92 95 85 80 75 by using a table to calculate
To calculate the variance and standard deviation using a table, you will need to calculate the mean first.
1. Calculate the mean:
Add up all the scores and divide by the number of scores.
(92 + 95 + 85 + 80 + 75) / 5 = 427 / 5 = 85.4
2. Calculate the variance:
Subtract the mean from each score, square the differences, add up all the squared differences, and divide by the number of scores.
[(92 - 85.4)^2 + (95 - 85.4)^2 + (85 - 85.4)^2 + (80 - 85.4)^2 + (75 - 85.4)^2] / 5 = (43.56 + 91.24 + 0.16 + 33.64 + 87.84) / 5 = 256.44 / 5 = 51.29
3. Calculate the standard deviation:
Take the square root of the variance.
√51.29 ≈ 7.164
Therefore, the variance of the scores is approximately 51.29 and the standard deviation is approximately 7.164.