Chapter 6, Problem 2PT

To determine

To calculate; the expected value of the total number of puzzles solved by the three subjects.

Answer to Problem 2PT

  $(d)6.9$

Explanation of Solution

The expected value can be calculated by taking summation of product of each possible event with its probability of occurrence.

  $\begin{array}{l}{\mu }_X={\displaystyle \sum _{}^{}xP(x)=1\times 0.2+2\times 0.4+3\times 0.3+4\times 0.1=2.3}\\ {\mu }_{3X}=3{\mu }_X=3(2.3)=6.9\end{array}$