PROBABILITY

Question 1:

(a) What are the characteristics of the standard normal distribution? (b) The HR department of an organization collects data on employees' age, salary, level of education, gender, and ethnicity. Which data do you think is more likely to follow a normal distribution? Explain why.

Question 2:

Learning Team Collaborative Discussion: Probability

Resource: Case Study 5.2 in Chapter 5 of Essentials of Business Statistics

Calculate the requested probabilities for items 1-3.

Discuss your findings for the probabilities.

• Identify the smoking trend from 1997-2007.
• Explain whether this is a discrete, continuous, or conditional probability.
• Explain how probabilities help you understand trends in data.

Recommend steps related to smoking behavior based on this trend.

Case Study 5.2

According to figures released by the New York City government, smoking among New York City teenagers is on a decline, continuing a trend that began more than a decade ago (The New York Times, January 2, 2008). According to the New York City Youth Risk Behavior Survey, the teenage smoking rate dropped to 8.5% in 2007 from about 17.6% in 2001 and 23% in 1997. City officials attribute the lower smoking rate to factors including a cigarette tax increase, a ban on workplace smoking, and television and subway ads that graphically depict tobacco-related illnesses.

In a report, use the above information to

1. Calculate the probability that at least one in a group of 10 New York City teenagers smoked in 2007.

2. Calculate the probability that at least one in a group of 10 New York City teenagers smoked in 2001.

3. Calculate the probability that at least one in a group of 10 New York City teenagers smoked in 1997.

4. Comment on the smoking trend between 1997 and 2007.