Answer:
[tex]E(x)=\$9.118[/tex]
Step-by-step explanation:
From the question we are told that:
Available bills
[tex]\$5=N0 9\\\\\$10=N0 5[/tex]
[tex]\$20=N0 3[/tex]
Therefore
Total Bills
[tex]n=5+9+3[/tex]
[tex]n=17[/tex]
Probability of selecting each bill
[tex]For\$5[/tex]
[tex]P(\$5)=\frac{9}{17}[/tex]
[tex]For\$10[/tex]
[tex]P(\$10)=\frac{5}{17}[/tex]
[tex]For\$20[/tex]
[tex]P(\$20)=\frac{3}{17}[/tex]
Generally the equation for Expected winning is mathematically given by
[tex]E(x)=\sum(X)*P(X)[/tex]
[tex]E(x)=5*\frac{9}{17}+10*\frac{5}{17}+20*\frac{3}{17}[/tex]
[tex]E(x)=\$9.118[/tex]