EXPLANATION
If the odds in favor are 7 to 5.
The expected value is a predicted value calculated by multiplying a value by its probability.
The probability is given by the following relationship:
[tex]\text{Probability}=\frac{\text{Odd in favor}}{\text{Total number of outcomes}}[/tex]In this case, odds in favor = 7
Total = 7 + 5 = 12
Replacing terms:
[tex]\text{Probability}=\frac{7}{12}=0.58[/tex]Now, we need to calculate the expected value by multiplying the Probability to the First Prize as shown as follows:
[tex]\text{Expected Value= 0.58}\cdot\text{ 36,000=2}1,000[/tex]Hence, the expected value is $21,000