1.A research study performed at checkout lines at Publix Supermarket in South Florida revealed that between 4pm and 7pm on weekdays there is an average of 4 customers waiting in line. What is the probability that you visit a Publix today during this period and find:
No customers waiting?
4 customers waiting?
4 or fewer customers waiting?
4 or more customers waiting?
2. A study on crime indicated that 3.1 car thefts occur each minute in the USA. Assume that the distribution of thefts per minute can be approximated by the Poisson probability distribution.
Calculate the probability that exactly 4 thefts occur in a minute
What is the probability there are no thefts in a minute?
What is the probability there is at least 1 theft in a minute?
3. The annual sales of playground equipment follow the normal distribution. However, the mean and standard deviation are unknown. 40% of the time sales are more than 470,000 and 10% of the time sales are more than 500,000.
Calculate the mean and standard deviation.