6. It is known that the diameter of Douglas fir trees is normally distributed with μ = 50cm and a 12cm. (a) What is the probability that a randomly selected Douglas fir tree has a diameter greater than 73cm? (b) What proportion of Douglas fir trees have diameter between 40 and 55cm? (c) Find the diameter, d, such that 30% of Douglas fir trees have diameters that exceed d.

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A: From the provided information, Sample size (n) = 22 Sample mean (x̄) = 125 Sample standard deviation…

Q: Customers arrive at a one-man barbershop according to a Poisson process with a mean inter-arrival…

A:

Q: f(t; B₁, B₂) = B1 B₂ · (e-P₁² - e-B₂¹) - B₂ - B₁

A:

Q: Assume that the readings on the thermometers are normally distributed with a mean of 0° and standard…

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Q: It is known that under ordinary conditions, 15% of people will not contract a certain disease.…

A: Obtain the mean of the normal distribution.   The mean of the normal distribution is obtained below…

Q: d. (**) Now suppose the supplier of workbenches guarantees KraftyCity that the lead time will be a…

A: Lead time L=3 weeks   Standard deviation σL=1.2 weeks Average weekly demand d=24 Standard…

Q: (b) Based on your answer to part (a), choose the correct statement. The value of the test statistic…

A: From the part a, The critical values are -1.645 and 1.645. Test statistic is 2.041.

Q: If a coefficient is not statistically significant, what does that mean? 1   There is omitted…

A: In the regression analysis, we want to test the significance of the model that means we want to see…

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A: To check which test is appropriate for examining the relationship between two scale variables.

Q: How do i get to .5594  in step 1 it makes no sense to me

A: The standard deviation of width is 0.914 and standard deviation of height is 1.634.

Q: ACT Scores A survey of 1000 students nationwide showed a mean ACT score of 21.4. A survey of 500…

A: given data x¯1  = 21.4σ1 = 3n1 = 1000x¯2  = 21.3σ2 = 3n2 = 500α = 0.10claim : μ1 > μ2

Q: ssume that a sample is used to estimate a population proportion p. Find the 99.9% confidence…

A: given data, CI=0.999α=1-0.999=0.001n=223p^=0.82

Q: The candlestick chart shows the performance of the stock of a technology company over a 10-day…

A:

Q: Test the claim that the proportion of men who own cats is significantly different than the…

A: From the provided information, nM=40p^M=0.45nF=60p^F=0.55 Level of significance (α) = 0.02

Q: A coin-operated drink machine was designed to discharge a mean of 9 fluid ounces of coffee per cup.…

A:

Q: Let p be the population proportion for the following condition. Find the point estimates for p and…

A: Given that X = 520.     and.     N = 1259

Q: EXAMPLE 6.56 If λ = 2 per hour and u = 4 per hour in a 2-capacity single- server queueing system,…

A:

Q: What is the total degree of freedom for the test?       A. 18       B. 17       C. 16       D. 15

A: Given that  There are three type of gasoline A , B and C. The litres per Kilometre for a random of 6…

Q: Consider the data. X₁ Y₁ 1 2 3 4 5 486 10 12 The estimated regression equation for these data is 9 =…

A: Given data: x y 1 4 2 8 3 6 4 10 5 12 The estimated regression line is:…

Q: A university interested in tracking its honors program believes that the proportion of graduates…

A: It is given that the proportion of graduates with a GPA of 3.00 or below is less than 0.20.

Q: Test the claim that the mean GPA of night students is larger than the mean GPA of day students at…

A: Given: Night students: n1 = 30 X1 = 2.8 s1 = 0.06 Day students: n2 = 30 X2 = 2.78 s2 = 0.07 Formula…

Q: If the lines of regression of Y on X and X on Y are respectively a₁ X + b₁Y+c₁ = 0 and a₂X + b₂Y+c₁₂…

A:

Q: Over the years, the mean customer satisfaction rating at a local restaurant has been 92. The…

A: Parametric test is used when the population follows the normal distribution. Some of the parametric…

Q: Benford’s Law is an observation about the leading digits of the numbers found in real-world data…

A:

Q: In a study of life expectancy in a certain region, the mean age at death was 70 years, and the…

A: given data  mean age at death (μ) = 70 yearsstandard deviation (σ) = 5 yearssample size (n) = 45

Q: 7. In this electric billiards game, the ball is so likely to fall to one side or the other after…

A: By classical definition of probability, the probability of an event is ratio of the number of cases…

Q: If the variance of the sum is Var(X+Y) = 6 and Var(X) = Var(Y) = 4, then what is the correlation…

A: given data  Var(X+Y) = 6 Var(X) = Var(Y) = 4 corr(X,Y) = ?

Q: We want to conduct a hypothesis test of the claim that the population mean score on a nationwide…

A: GIVEN DATA, HYPOTHESIS TEST: claim :μ≠510x¯=505s=77we have to find out the test statistics for the…

Q: Before After 6.9 6.3 3.6 2.1 7.3 7.1 12.8 8.6 8.5 8.2 10.1 6.4 8.4 3.9 5.2 2.1

A: We find the differences of ‘before’ and ‘after’. di= Xi-Yi

Q: Classify the below if they are examples of descriptive or inferential statistics: Prompts…

A:

Q: To estimate the portion of voters who plan to vote for Candidate A in an election, a random sample…

A: The value of the margin of error given is 3 percent. The value of the confidence interval given is…

Q: A waiter believes the distribution of his tips has a model that is slightly skewed to the left, with…

A: given data slightly left skewed distribution μ = 8.30σ = 5.90n = 50 heren>30; as per clt sampling…

Q: If the Cumulative Gain at a depth of 15% for the Neural Network model is converted to number of…

A: Cumulative gain is used to examine or evaluate the performance of a specific or particular model on…

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A: Given that Population Mean=500 Population standard deviation =100 We have to find the probability…

Q: You have 100 people take two tests, A and B. You find that 40 people score above average on Test A…

A: Given that 100 people take two test : A and B.

Q: Using the Little's formula, obtain the average waiting time in the system for M/M/1/N model.

A:

Q: EXAMPLE 6.10 A duplicating machine maintained for office use is operated by office assistant. The…

A:

Q: Many people are members of walking clubs. You believe that the average speed of walkers at the…

A: Solution: Given information: n=36 Sample size x =4.18  Sample mean s=0.64 Sample standard deviation…

Q: Soft Drink Consumption A researcher claims that the average yearly consumption of soft drinks per…

A: given data,claim:μ=52n=59x¯=53.3σ=3.5α=0.10

Q: A population of values has a normal distribution with μ=113.6 and σ=14. You intend to draw a random…

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Q: Drug Effects: A new muscle relaxant is available. Researchers from the firm developing the relaxant…

A: Given: μ = 38 σ = 5 n = 10 X = 35 Formula Used: Z = X-μσn

Q: Medium Lead Level High Lead Level 72 n₂ = 11 99 92 X₂ = 89.615 S2 = 10.573 85 84 97 83 92 104 111 91

A:

Q: Consider an M/M/1 queueing system. If λ = 6 per hour and μ = 8 per hour find the probability of at…

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Q: The amount of time that a customer spends waiting at an airport check-in counter is a random…

A: Given,sample size(n)=49mean(μ)=10.2standard deviation(σ)=1.5

Q: Consider an M/M/1 queueing system. Find the probability of finding at least n customers in the…

A:

Q: The diameter of steel rods manufactured on two different extrusion machines is being investigated.…

A: Method: If p-value is less than the level of significance (alpha) . Then we reject the null…

Q: The average weight of new-born kittens is 3.5 ounces. A breeder suspects one of her cats, Stella,…

A: Histogram are used to determine the shape of the data. It explain whether it is skewed or not. Steam…

Q: An article in the Los Angeles Times (Dec. 3, 1993) reports that 1 in 200 people carry the defective…

A: Given information: PDefective gene=1200=0.005 n = 2000

Q: 20. What are the Level of Measurement of the statistical variables? Nominal, Ratio, Interval, or…

A:

Q: A croissant shop produces two products: bear claws (B) and almond-filled croissants (C). Each bear…

A: by bartleby policy i can gives only 3 subparts answers at a time   Suppose, number of bear claws…