-140 reservations for single rooms were made for a hotel. Assuming each person will not show up with 11% :
a) What is the probability that 127 single rooms are NOT enough?
b) What assumptions are necessary that we can calculate the answer of a) ?

-A normal distribution has the 14% quantile equal to 25 and the 91% quantile equal to 38.
Find the mean and the standard deviation of that normal distribution.

-We assume that the arrivals in a shop follow a Poisson process.
In 40 minutes on average 28 people arrive. Calculate the probability
that the waiting time for the 4th event is larger than 9.54 minutes.