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Normal Distribution

Normal Probability Distributions Values

Applying Continuity Correction - The given values are discrete. Use the continuity correction and describe the region of the normal distribution that corresponds to the indicated probability. Probability of at least 12 adult males on an elevator in the Empire State Building Probability that the number of working vending

Probability Based on Normal Distribution of Flu Symptoms

Cholesterol Reducing Drug - The probability of flu symptoms for a person not receiving any treatment is 0.019. In a clinical trial of lipitor, a common drug used to lower cholesterol, 863 patients were given a treatment of 10-mg atorvastatin tablets, and 19 of those patients experienced flu symptoms (based on data from Pfizer, i

Statistics - Normal Distribution, Statistical test

1. The net profit of an investment is normally distributed with a mean of $10,000 and a standard deviation of $5,000. The probability that the investor's net gain will be at least $5,000 is _____________. a) 0.4967 b) 0.8413 c) 0.1859 d) 0.3413 2. A company believes that it controls more

Business Math

1 Research the typical categories of retirement annuity plans? 2. what is a 401 (k) plan? What is a Roth IRA ? How are they different ?Why were they developed? 3. How do they work? 4. Compare and contrast the features of the two types of retirement plans? 5. What are the advantages of pa

Statistics - Geometric Distribution and Poisson Distribution

Question 1 The probability that you will make a sale on any given telephone call is 0.23. What is the probability that you do not make any sale on the first three calls? [Hint: geometric distribution] a. 0.105 b. 0.543 c. 0.457 d. 0.186 Question 2 The mean number of typographical error per page of a newspaper is 3. What

Probability: Normal and Binomial Distributions

1. A component in a subsystem has a reliability factor of .9999 during a Shuttle mission. There is redundancy so as long as fewer than 2 of the components fail, the subsystem will operate. What is the probability that there will be 2 or more failures? 2. A video tube has a mean life of 2000 hours with a standard deviation of

Questions About Probabilities and Normal Distributions

A famous restaurant owner noticed that in the past 20 years his hamburger supply shows a normal distribution in weight. Average weight was 10.0 ounces with a standard deviation of 0.3 ounces after they were cooked. (Consider normal distribution) * What is a probability that a customer gets a hamburger that weighs at least 10.

Multiple Choice

Question 1. If you have a normal distribution of a random variable x, with a mean of 56 and standard deviation of 8: What is the probability that the random variable x will be within plus or minus 1 standard deviation of the mean? a. 0.682 b. 0.75 c. 0.00 Question 2 What is the probability that x is greater than 64?

Normal Distribution and Proportion of Scores. The solutions are given with each minute detail of their solution steps. These step by step solutions will help students to work out other similar problems on their own efforts.

Question (1) Scores on WAIS approximate a normal curve with a mean of 100 and standard deviation of 15. What proportion of scores are (i) Above 125 ? (ii) Below 82 ? (iii) Within 9 points of the mean ? (iv) More than 4o points from the mean ? Question (2) Scores on WAIS test approximately normal with a mean of 100 and

Business Statistics -problems on two-sigma control limits, p charts, c charts

10. A travel agency is concerned with the accuracy and appearance of itineraries prepared for its clients. Defects can include errors in times, airlines, flight numbers, prices, car rental information, lodging, charge card numbers and reservation numbers, as well as typographical errors. As the possible number of errors is nearl

Probability questions on Binomial and normal distribution

1. Assume a restaurant business succeeds 60% of the time. Suppose that there are three such restaurants open in your city. When they don?t compete with one another, it is reasonable to believe that their relative success would be independent. [Hint: use binomial probability distribution function in Megastat or Phstat] A) Wha

Inventory Models

Managers at Wager Fabricating Company are reviewing the economic feasibility of manufacturing a part that it currently purchases for a supplier. Forecasted annual demand for the part is 3200 units. Wagner operates 250 days per year. Wagner's financial analysts have established a cost of capital of 14% for the use of funds f


1. MCQ: The first test in Introductory Algebra had a mean of 82 with a standard deviation of 15. If a student made a 94 on the test, what is the corresponding z-score? a) -0.58 b) -0.47 c) 0.47 d) 0.80 e) NOT 2. Students are sorted according to sex (male, female), grade level (lower division, up

Standard deviation of the winning percentages in a league: Compare the 5 values of standard deviation that you determined for each league. What does this suggest about competitive balance in the two leagues? Explain.

A) For the two hypothetical leagues represented below calculate the league standard deviation (s t) of the winning percentage (wti) for each year. {Where wti is the winning percentage of team i in year t; st is the standard deviation of the winning percentages in one of the leagues in year t; and w is calculated as the number of

Long distance calling and food expenditures based on a normal distribution

Problem 1 A recent report in USA Today indicated a typical family of four spends $490 per month on food. Assume the distribution of food expenditures for a family of four follows the normal distribution, with a mean of $490 and a standard deviation of $90. a. What percent of the families spend more than $30 but less than $490

Sample Mean and Standard Deviation of a Manufacturer

Please help me with an assignment by answering the following: A manufacturer claims that the life span of its products is normally distributed, with a mean of 21.9 hours and a standard deviation 102 hours. A test is made of 20 products and the sample time are shown below. Find the mean and the standard deviation of the sample

Finding the p-value

Ms. Lisa Monnin is the budget director for nexus media inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample information: Sales ($): 131,135,146,165,136,142 Audit ($): 130,102,129,143,149,120,139 At the .10 significance level, can she conclude

Random Walk Theory and Normal Distribution

Attached is the daily closing price of the stock (xmsr). Decide whether the data appears to be normally distributed by: 1. Record the daily changes in the closing stock price of each day. a) Make a stem and leaf display, histogram or polygon, and box and whisker plot. b) Evaluate the actual versus theoretical properti

Assumptions of various tests

1. What are the only three ways to setup the Hypothesis (Ho & H^)? ( the last symbol "^" is in the bottom of the H) 2. What are the assumptions regarding a large one sample z-test and what Excel aid would you use to perform the test, Data Analysis or MacDolt? 3. What are the assumptions regarding a small one sample t-test

Normal distribution

If 65% of the population of a large community is in favor of a proposed rise in school taxes, approximate the probability that a random sample of 100 people will contain a) at least 50 who are in favor of the proposition b) between 60 and 70 inclusive who are in favor c) fewer than 75 in favor

Binomial distribution of home runs

In 1998, Mark McGwire of the St. Louis cardinals hit 70 home runs, a new Major League record. Was this feat as surprising as most of us thought/ In the three seasons before 1998, McGwire hit a home run in 11.6% of his times at bat. He went to bat 509 times in 1998. If he continues his past performance, McQwire's home run count i

Operations Research and Economic Order Quantity

A product sold by Home Depot, Inc., with an annual demand of 1000 units has Co = $25.50 and Ch = $8. The demand exhibits some variability such that the lead-time demand follows a normal probability distribution with µ = 25 and standard deviation = 5. a. Determine the recommended order quantity. b. Determine the reorder p

Normal Distribution and Marketing

When is understanding the normal distribution and the factors that affect its shape important in solving business and marketing-related questions? Explain with a simple example.

Determine the probability the sample mean

The mean television viewing time for Americans is 15 hours per week (Money, November 2003). Suppose a sample of 60 Americans is taken to further investigate viewing habits. Assume the population standard deviation for weekly viewing time is 4 hours. a. Determine the probability the sample mean will be within 1 hour of the pop

Random numbers

A normal distribution has a mean of 500 and a standard deviation of 50. A manager wants to simulate 2 values from this distribution, and has drawn these random numbers: -0.6 and 1.4. What are the 2 values respectively?

Expectation of normal distribution

I know this problem is very easy, finding E(x) from the distribution function. I tried to do it by integration by parts, one way I took x to be my first function and the whole exp term to be my 2nd function, but it didn't work, then I split the exponential term to 2 terms combined one with x as my first function and took the sec