Calculate the mean number of hours in downtime

Assignment Help Basic Statistics
Reference no: EM13944058

1. The incomes of all families in a particular suburb can be represented by a continuous random variable.  It is known that the median income for all families in this suburb is $60,000 and that 40% of all families in the suburb have incomes above $72,000.  

a) For a randomly chosen family, what is the probability that its income will be between $60,000 and $72,000? 

b) Given no further information is available, what can be said about the probability that a randomly chosen family has an income below $65,000? 

 

2. A portfolio manager has asked you to analyze a newly acquired portfolio to determine its value and variability.  The portfolio consists of 50 shares of Alpha Music and 40 shares of Beta Shows.  Analysis of past history indicates that the share price of Alpha Music has a mean of $25 and variance of 121.  Similarly, Beta Shows has a mean share price of $40 with a variance of 225.  Your best evidence indicates that the share prices have a correlation coefficient of +0.5.  

a) Compute the mean value and variance of the portfolio. 

b) If the correlation coefficient between the share prices were actually  - 0.5, what would be the mean value and the variance of the portfolio? 

3. A manufacturer of network computer server systems is interested in improving the customer support service. As a first step, its marketing department has been charged with the responsibility of summarizing the extent of customer problems in terms of system downtime. The 40 most recent customers were surveyed to determine the amount of downtime in hours they had experienced in the previous month. The survey data are shown below.

a) Using the appropriate formula for grouped data, calculate the mean number of hours in downtime.

b) Using the appropriate formulas for grouped data, calculate the variance and the standard deviation.

c) Calculate the Coefficient of Variation

Reference no: EM13944058

Questions Cloud

How could a dishonest purchasing agent cheat his company : Suppose a purchasing agent receives the goods that he purchases and also approves payment for the goods. How could a dishonest purchasing agent cheat his company? How do companies avoid this internal control weakness?
Find the expected value of this lottery game : The Delaware Lottery is offering customers a chance to win $10,000. Customers pay $5.00 for a ticket (there are 3000 tickets sold only). Second prize is $1,000. If a customer buys only one ticket, find the expected value of this lottery game.
Developing a strategic and co-ordinated approach : Description: Write a formal research essay that critically discusses the following statement: "It is important to develop a strategic and co-ordinated approach to developing and staging events in a region.
Write a letter of inquiry to a utility company : Write a letter of inquiry to a utility company, a safety or health care agency, or a company in your town, and ask for a brochure or an annual report describing its services to the community
Calculate the mean number of hours in downtime : Using the appropriate formula for grouped data, calculate the mean number of hours in downtime. Using the appropriate formulas for grouped data, calculate the variance and the standard deviation.
Write argument-should college campuses ban alcohol on campus : Construct three different arguments that pertain to the issue, each a paragraph long. It will be easy to come up with one argument for and one against the issue of your choice, but you must also come up with a third argument.
Competitive market in respect to efficiencies : Outline: the cop nay is facing a challenge in a very competitive market in respect to efficiencies within its operational environment, in particular the Sales Admin, Warehouse and Logistical areas, which has resulted in loss of orders.
What are digital downloads and digital compression : What can be digitally downloaded and compressed?
At this website you willfind ceo salaries : http://www.aflcio.org/Corporate - Watch/CEO Pay and-the -99 At this website you willfind CEO Salaries as reported by the AFL-CIO. Pick a company and report yourfindings. Be sure to include not only remuneration in money terms but also the stockoption..

Reviews

Write a Review

Basic Statistics Questions & Answers

  Issue of statistical power in non-parametric tests

Discuss the issue of statistical power in non-parametric tests (as compared to their parametric counterparts). Which type tends to be more powerful? Why?

  1 a random sample of 60 college graduates results in a mean

1 a random sample of 60 college graduates results in a mean time to graduate of 4.58 years with a standard deviation of

  Median of the sample or average

Write down the probability of that the median of the sample or average medians is greater or more than 320 minutes?

  State the null and alternate hypotheses

State the Null and Alternate Hypotheses. Customize your hypothesis to the business problem context (do not usegenericterms).

  State the decision rule

State the decision rule? (Negative amount should be indicated by a minus sign. Round your answers to 3 decimal places.)

  For example the probability that the economy will be in

suppose that the percentage annual return you obtain when you invest a dollar in gold or the stock market is dependent

  Preceding period-matrix of transition probabilities

find the product of the vector of state probabilities for the preceding period and the matrix of transition probabilities.

  In a study conducted by a local university it was found

in a study conducted by a local university it was found that 25 of college freshmen support increased military

  In 2010 433428 adult texans were diagnosed with diabetes

according to the texas department of state health services there are approximately 17.7 million adults age 18 living in

  Conclusion of the new mean

Note that Σ x  = 2233 and Σ x 2   = 138,053. At the 5% level of significance, can the instructor conclude that the new mean is different from 64?

  Does the difference between the probabilities of parts a

an insurance company found that 2.5of male drivers between theages of 18 and25 are involved in serious accidents

  Standard deviation and coefficient of variation

What is the probability that a respondent chosen at random - Enjoys his or her role in the organization?

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd