Step 1 :The mean of a probability distribution is calculated by multiplying each possible outcome by its probability and then summing these products. In this case, we need to multiply each value of x (number of activities) by its corresponding probability and then sum these products to get the mean.
Step 2 :Let's denote the number of activities as x and their corresponding probabilities as P(x). The values of x are [0, 1, 2, 3, 4] and the corresponding probabilities are [0.079, 0.228, 0.145, 0.156, 0.392].
Step 3 :We calculate the mean by multiplying each x value by its corresponding probability and summing these products: \(0*0.079 + 1*0.228 + 2*0.145 + 3*0.156 + 4*0.392\).
Step 4 :The mean of the random variable x is approximately 2.554.
Step 5 :Final Answer: The mean of the random variable \(x\) is \(\boxed{2.554}\). This means that on average, a parent of a 6th- to 8th-grade student is involved in approximately 2.554 activities.