Final answer:
The mean of a dataset is computed by summing all values (Σx) and then dividing by the count of those values (n), which is represented by the formula Σx/n.
Step-by-step explanation:
The formula for computing the mean is given by option c, which is Σx/n. In words, ΣX represents the sum of all the values in the dataset, divided by the number of observations (n). This is a fundamental concept in statistics used to calculate the average value of a dataset.