Question

The following probability distribution is for the random variable X= number of classes for which full timestudents at a university are enrolled in a semester:No. of classes, XProbability40.250.560.270.1What is the mean number (expected value) of courses taken perstudent?

Answer 1

The expected value is given by,

$E(x)=\sum ^{}_{}X_iP(X_i)$

Here, P(Xi ) is the probabilty of X.

Therefore, the expected value of the given probability distribution can be calculated as:

$\begin{gathered} E(X)=4\times0.2+5\times0.5+6\times0.2+7\times0.1 \\ _{}E\mleft(X\mright)=5.2 \end{gathered}$

Therefore, the expected value of course taken by the student is 5.2.