Respuesta :
Total number of tickets is one thousand.
Formula for probability is given below as,
[tex]\text{Prob}=\frac{required\text{ outcome}}{total\text{ outcome}}[/tex]Probability of one $1000 prize is given below as,
[tex]P(\text{\$1000)=}\frac{1}{1000}[/tex]Probability of one $400 prize is given below as,
[tex]P(\text{\$400)=}\frac{1}{1000}[/tex]Probability of ten $100 prize is given below as,
[tex]P(\text{\$100)=}\frac{10}{1000}=\frac{1}{100}[/tex]For the expected value if each person buys one ticket,
[tex]\begin{gathered} Expected\text{ value=}(\frac{1}{1000}\times1000)+(\frac{1}{1000}\times1000)+(\frac{1}{100}\times1000) \\ \text{Expected value=}(1+1+10)=\text{\$12} \end{gathered}[/tex]Expected value is $12
