Probability and statistics exercise

  Question 5. The time (in minutes) between arrivals of customers to a bank is modelled by the Exponential distribution with mean 0.52. a) What is the probability that the time between consecutive customers is less than 15 seconds? b) Find the probability that the time between consecutive customers is between 10 and 15 seconds. c) Given that the time between consecutive customers arriving is greater than 10 seconds, what is the chance that it is greater than 15 seconds? Question 7. The number of burgers consumed per month by college students is normally distributed with a mean of 11 and a standard deviation of 3. a) What proportion of college students consume more than 12 burgers per month? b) What is the probability that in a random group of 8 students, a total of more than 80 burgers are consumed?