Chapter 8.1, Problem 27E

A store carries four brands of DVD players: $J,G,P$ , and $S$. From past records, the manager found that the relative frequency of brand choice among customers varied. Which of the following probability assignments for a particular customer choosing a particular brand of DVD player would have to be rejected? Why?

$\left(\text{A}\right)P\left(J\right)=.15,P\left(G\right)=-.35,P\left(P\right)=.50,P\left(S\right)=.70$

$\left(\text{B}\right)P\left(J\right)=.32,P\left(G\right)=.28,P\left(P\right)=.24,P\left(S\right)=.30$

$\left(\text{C}\right)P\left(J\right)=.26,P\left(G\right)=.14,P\left(P\right)=.30,P\left(S\right)=.30$