Question

question 1
5 points
the value of one score in a distribution is changed from x = 20 to x = 30. which measure(s) of central tendency is (are) certain to change
a mode
b median
c mean
d mean and median

Explanation:

The mode is the most frequently - occurring value, and changing one non - modal value won't change it. The median is the middle value when data is ordered. If the position of the changed value doesn't affect the middle position (e.g., in an odd - sized dataset where the changed value is not the middle one), the median may not change. The mean is calculated as $\frac{\sum_{i = 1}^{n}x_{i}}{n}$. Changing one value will change the sum $\sum_{i = 1}^{n}x_{i}$, and thus the mean will change.

Answer:

C. Mean