Question

by how much will the mean vary if the outlier is included? 79, 69, 81, 73, 38, 86, 68

Explanation:

Step1: Identify the outlier

The outlier is 38 (it is much lower than other values).

Step2: Calculate mean with outlier

Sum all values: $79 + 69 + 81 + 73 + 38 + 86 + 68 = 494$
Mean: $\frac{494}{7} \approx 70.57$

Step3: Calculate mean without outlier

Sum values excluding 38: $494 - 38 = 456$
Mean: $\frac{456}{6} = 76$

Step4: Find the difference

Subtract the two means: $76 - 70.57 \approx 5.43$, rounded to 5.4

Answer:

C. 5.4