It has been reported that the average U.S. office worker receives 14 fax messages per day. For purposes of the exercise, we will assume that the daily number of fax messages in normally distributed with a standard deviation of 5.0 messages. For an office in which 10 workers are employed, and considering these persons as a simple
15.28 Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At alpha = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify your favorite brand in this k
How many passengers are on the cruises with the fewest In establishing warranties on HDTV sets, the manufacturer wants to set the limits so that few will need repair at manufacturer expense. On the other hand, the warranty period must be long enough to make the purchase attractive to the buyer. For a new HDTV the mean number of
Show work in Excel or Megastat. 10.32 A 2005 study found that 202 women held board seats out of a total of 1,195 seats in the Fortune 100 companies. A 2003 study found that 779 women held board seats out of a total of 5,727 seats in the Fortune 500 companies. Treating these as random samples (since board seat assignments chan
A sociologist wants to determine if the life expectancy of people in Africa is less than the life expectancy of people in Asia. The data obtained is shown in the table below. Africa:Sample mean 55.3,Population standard deviation 8.1, sample size 53 Asia: Sample mean 65.3, Population standard deviation 9.3
Calculate GM's Altman Z-Score. Show your calculations. Based on the Z- Score: Do you predict that GM will go bankrupt in the near-term? Explain Based on your calculations, would you agree or disagree with Lutz that GM is over the worst? Explain in detail.
Comparing Scores. 3 students take equivalent test of a sense of humor and, after the laughter dies down, their scores are calculated which score is in the middle of the other two? 1. A score of 144 on a test with a mean of 128 and a standard deviation of 34? 2. A score of 90 on a test with a mean of 86 and a standard de
Low Activity High Activity N1=10,239 n2=9,877 X1=101 X2=56 Assume that you plan to use a significance level of a=.05 to test the claim that P1=P2. Use the given sample sizes and number of successes to find the value of the z statistic.
This exercise is a "what if analysis" designed to determine what happens to the test statistics and interval estimates when elements of the statistical inference change. This can be solved manually or on Excel with Test statistics or Estimators workbook. Random samples from two binomial populations produced the following stat
The weight for a group of 18 month-0ld girls are normally distributed with a mean of 24.4 pounds and a standard deviation of 2.6 pounds. Use the table to find the percentage of 18 month-old girls who weigh more than 27.8 pounds. z-score1. 0.1, 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Percentile 53.98, 57.9,
What is the relationship between the Z-score for Normal Distribution and Continuous Probability?
Find the sample proportions and test statistic for equal proportions. Is the decision close? Find the p-value. a. Dissatisfied workers in two companies: x1 = 40, n1 = 100, x2 = 30, n2 = 100, α = .05, twotailed test. b. Rooms rented at least a week in advance at two hotels: x1 = 24, n1 = 200, x2 = 12, n2 = 50, α
Length of Pregnancy. A woman wrote to Dear Abby and claimed that she gave birth 308 days after a visit from her husband, who was in the Navy. Kengths of pregnancies have a mean of 268 days and a standard deviation of 15 days, Find the z score for 308 days. Is such a length unusual? What do you conclude?
Please see the attached file. Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At α = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify y
Please solve using the 5 step procedure for Hypothesis testing. In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents, while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents.
At a large university, 500 freshmen take their final exam for their marketing course. Scores are normally distributed with a mean 79 and standard deviation 7. What is the probability of a score, X, falling between 73 and 83?
Who would use Altman's Z score to predict bankruptcy? Why would the ability to predict bankruptcy be useful to them?
Please see the attached file.
A distribution has a standard deviation of 0=4. Find the z-score for each of the following locations in the distribution. a. Above the mean by 4 points b. Above the mean by 12 points c. Below the mean by 2 points d. Below the mean by 8 points
In Dallas some fire trucks were painted yellow. During the test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents. the fleet of yellow trucks made 135,035 runs and had 4 accidents. At a=.01, did the yellow fire trucks have a significantly lower accident rate? Zc=2.326 Z=2.961 p-value=.0015 normal
Problem 1: The Web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal, using α = .025? Problem 2: An auditor reviewed 25 oral surgery insuran
Lewis earned 85 on his biology midterm and 81 on his history midterm. In the biology class the mean score was 79 with standard deviation 5. In the history class the mean score was 76 with standard deviation 3. a) Convert each midterm score to a standard z score. b) On which test did he do better compared to the rest of t
Please help with the following statistics problem. A sample of 36 observations is selected from a normal population. The sample mean is 21, and the population standard deviation is 5. Conduct the following test of hypothesis using the .05 significance level. H0: µ (less than or equal to) 10 H1: µ >10 a. State the
An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the ave
A coin was flipped 60 times and came up heads 38 times. (a) At the 0.10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.
We are using a chart on standard normal (z) distribution: cumulative area from the LEFT showing Negative x Scores on one side and Positive (z) scores on the other. a. P(z>2.61). b. P(-1.62 < z < 2.81). c. The z-score that would create a right tail of 31%. d. The z-score that would create a left tail of 6.5%.
#1 With regards to a standard normal distribution complete the following: (a) Find P(z < 0), the percentage of the standard normal distribution below the z-score of 0. (b) Find P(z < 1.65), the percentage of the standard normal distribution below the z-score of 1.65 (c) Find P(-3 < z
The Environmental Protection Agency (EPA) fuel economy estimates for automobile models tested recently predicted a mean = 24.8 miles per gallon and a standard deviation a = 6.2 miles per gallon for highway driving. Assume a normal distribution. Use this information to answer questions #13 - #14. (13) Use Table 4 (Standard
9.22 The mean arrival rate of flights at O'Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. (a) Set up a rig
10.2 Find the sample proportions and test statistic for equal proportions. Is the decision close? Find the p-value. a. Dissatisfied workers in two companies: x1 = 40, n1 = 100, x2 = 30, n2 = 100, α = .05, two tailed test. b. Rooms rented at least a week in advance at two hotels: x1 = 24, n1 = 200, x2 = 12, n2 = 50, &#