Answer
B. The statement makes sense because the expected value after ten rolls is -333.33 dollars, which is less than the value of the current bill
Step-by-step explanation
The expected value per bet is calculated as follows:
[tex]\text{ Expected value \lparen per bet\rparen }=p(winning)\times amount\text{ won}-p(losing)\times amount\text{ lost}[/tex]
There are 6 outcomes when rolling a die, then the probability of rolling a 1 or a 2, the probability of rolling a 3, and the probability of rolling a 4 or a 5 or a 6 is:
[tex]\begin{gathered} p(rolling\text{ 1 or 2})=\frac{2}{6}=\frac{1}{3} \\ p(roll\imaginaryI ng\text{ 3})=\frac{1}{6} \\ p(roll\imaginaryI ng\text{ 4 or 5 or 6})=\frac{3}{6}=\frac{1}{2} \end{gathered}[/tex]
You win $700 for rolling 1 or 2, $200 for rolling 3, and you lose $600for rolling 4, 5, or 6, then the expected value per bet is:
[tex]\begin{gathered} \text{ Expected value \lparen per bet\rparen }=\frac{1}{3}\times\text{ \$}700+\frac{1}{6}\times\text{ \$2}00-\frac{1}{2}\times\text{ \$6}00 \\ \text{Expected value }\operatorname{\lparen}\text{per bet}\operatorname{\rparen}=-\text{ \$}33.33 \end{gathered}[/tex]
You have to expect to lose $33.33 per bet. After 10 bets, the expected value is:
[tex]\begin{gathered} \text{ Expected value = number of bets}\times Expected\text{ }value\text{ per bet} \\ Expected\text{ }value=10\times-\text{ \$}33.33 \\ Expected\text{ v}alue=-\text{ \$}333.33 \end{gathered}[/tex]