Answer:
The expected revenue of the tour operator is 985.
Step-by-step explanation:
There are two outcomes:
Either less than 21 tourists show up and the operator does not have to pay anything. Or 21 tourists show up and the operator has to repay 100.
Anyways, initially he gets the price of all the tickets sold. That is 21 each at 50, so .
Then, we need to find the probability that all of the 21 tourists show up. In this case, we have to subtract 100 from the revenue.
Each tourist has a 0.02 probability of not showing up. This means that each has a 1-0.02 = 0.98 probability of showing up. So the probability P that all 21 tourists show up is .
So, the expected revenue of the tour operator is
Rounded up, the expected revenue of the tour operator is 985.