Question

Find the mean of the following Data set {72, 73, 55, 67, 80, 73, 77, 63, 67} Round to the nearest hundredth if necessary
Mean = __

Find the deviation of each data point from the mean for the following data set: {72, 73, 55, 67, 80, 73, 77, 63, 67}

Find the average deviation of the data set {72, 73, 55, 67, 80, 73, 77, 63, 67}. Round to the nearest hundredth if necessary.
Average deviation = __

Answer 1

Mean = 69.67 (627/9 = 209/3 ≈ 69.6667)

Deviations (x − mean), rounded to two decimals:
- 72: 72 − 69.67 = 2.33
- 73: 73 − 69.67 = 3.33
- 55: 55 − 69.67 = −14.67
- 67: 67 − 69.67 = −2.67
- 80: 80 − 69.67 = 10.33
- 73: 73 − 69.67 = 3.33
- 77: 77 − 69.67 = 7.33
- 63: 63 − 69.67 = −6.67
- 67: 67 − 69.67 = −2.67

Average deviation (mean absolute deviation):
Sum of absolute deviations = 160/3 ≈ 53.3333, so average = (160/3)/9 = 160/27 ≈ 5.9259 → 5.93

Average deviation = 5.93