Answer:
3 tokens.
Step-by-step explanation:
We need the roulette image, therefore we will suppose one that I will leave as an attached image:
The main thing to keep in mind in this case is that the probabilities are the same, therefore you don't have to take that into account, just operate with the values of each sector, therefore the expected value would be:
expected value = profit - loss
expected value = (5 + 5) - (4 + 3)
expected value = 10 - 7 = 3
This means that the number of tokens waiting for the student to earn for each spin is 3 tokens.