Final answer:
The expected value of a discrete random variable can be calculated by multiplying each value of the random variable by its probability and adding the products. In this case, the expected value of X is 1.1.
Step-by-step explanation:
The expected value/mean of a discrete random variable X can be calculated by multiplying each value of the random variable by its probability and adding the products. In this case, we have the following data:
x
P(X = x)
3
0.2
4
0.2
5
0.2
6
0.1
7
0.3
To find the expected value, we multiply each value of x by its corresponding probability:
E(X) = 3(0.2) + 4(0.2) + 5(0.2) + 6(0.1) + 7(0.3) = 1.1
Therefore, the expected value of X is 1.1.