Question

Suppose that the PDF for the number of years it takes to earn a Bachelor of Science (B.S.) degree is given as in Table $4.34$

On average, how many years do you expect it to take for an individual to earn a $B.S.$?

Short answer

On average, it takes $4.85$years to earn a B.S. degree.

Step-by-step solution

Given information

Given a table for PDF for the number of years it takes to earn a Bachelor of Science.

Explanation 

$X$	$P\left(X\right)$	$X.P\left(x\right)$
$3$	$0.05$	$0.15$
$4$	$0.40$	$1.60$
$5$	$0.30$	$1.50$
$6$	$0.15$	$0.90$
$7$	$0.10$	$0.70$
Total	$1$	$4.85$

$$\begin{gathered} E\left(x\right)=\underset{}{\sum \left[x.p\left(x\right)\right]} \\ E\left(x\right)=4.85 \end{gathered}$$

A person's expected time to complete a B.S. is $4.85$ years.