Answer:
A) -$3.16; B) A $15 on the number 34
Step-by-step explanation:
To find the expected value, we multiply the probability of winning by the amount won, multiply the probability of losing by the amount lost, and add the two.
The probability of winning is 5/38 and the net profit will be $75:
5/38(75) = 375/38 ≈ $9.87
The probability of losing is 33/38 and the amount lost will be $15:
33/38(-15) = -495/38 ≈ -$13.03
We now add these amounts:
9.87+-13.03 = -3.16
Since the expected value on a single number is -$0.79 and the expected value on any one of the given numbers in the set is -$3.16, the safer bet would be on the number 34.