Question

In a certain city, projections for the next year indicate there is a 20% chance that electronics jobs will increase by 1200, a 50% chance that they will increase by 300 and a 30% chance they will decrease by 700. Find the expected change in the number of electronics jobs in that city in the year.

Answer 1

We have the next information

`\begin{gathered} X=1200\rightarrow P(X)=0.2 \\ X=300\rightarrow P(X)=0.5 \\ X=-700\rightarrow P(X)=0.3 \end{gathered}`

So, the the expected change is

`\begin{gathered} 1200(0.2)+300(0.5)-700(0.3) \\ =240+150-210=180 \end{gathered}`

Finally, the expected change in the number of electronics jobs in that city in the year is 180