Homework 5
Answer the questions below in Excel, with one question on a separate spreadsheet. Submit one Excel workbook.
1.Students in the new MBA class at a state university has the following specialization profile: Finance-67, Marketing-45, Operations and Supply Chain Management-51, Information Systems-18. Find the probability that a student is either a finance or marketing major. Are the events finance specialization and marketing specialization mutually exclusive? If so, what assumption must be made?
2.An airline tracks data on its flight arrivals. Over the past 6 months, 50 flights on one route arrived early, 150 arrived on time, 25 were late, and 45 were canceled.
a.What is the probability that a flight is early? On time? Late? Canceled?
b.Are these outcomes mutually exclusive?
c.What is the probability that a flight is either early or on time?
3.A survey of 200 college graduates who have been working for at least 3 years found that 90 owned only mutual funds, 20 owned only stocks, and 70 owned both.
a.What is the probability that an individual owns a stock? A mutual fund?
b.What is the probability that an individual owns neither stocks nor mutual funds?
c.What is the probability that an individual owns either a stock or a mutual fund?
4.Row 26 of the Excel file Census Education Data gives the number of employed persons having a specific educational level.
a.Find the probability that an employed person has attained each of the educational levels listed in the data.
b.Suppose that A is the event “has at least an Associate’s Degree” and B is the event “is at least a high school graduate.” Find the probabilities of these events. Are they mutually exclusive? Why or why not? Find the probability P(A or B).
5.Use data National Income.xlsx, which sampled the income of 500 respondent in a county.
a.Apply the Histogram function in Data Analysis to plot the frequency distribution of national income in the sample
b.Apply the Descriptive Statistics function in Data Analysis to obtain the descriptive stats of national income in the sample
c.Based on the histogram and descriptive stats, what is the likely distribution of the in the sample?
d.Use Excel functions to find:
i.What is the range of values that are about two standard deviations (SD) from the mean?
ii.What is the probability that a person’s income falls within 2 SDs from the mean?
iii.What is the approximate probability that a person’s income is more than 100,000?
iv.What is the level of income that is lower than about 90% of the population in the country?
v.What is the level of income that is higher than about 99% the population in the country?
