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a. P(x < 25 | μ = 27 and σ = 3) b. P(x ≥ 66 | μ = 50 and σ = 7) c. P(x > 44 | μ = 50 and σ = 5) d. P(20 < x < 27 | μ = 25 and σ = 3) e. P(x ≥ 85 | μ = 70 and σ = 2.87) z-score x Mean StDev n 1 5
z=(x-μ)/σ 70 Mean
St Dev 50 Mean
- Suppose 4 St Dev
- Scores on a certain exam are normally distributed with a mean of 90 and a variance of 25. What is th z value 80 mean 90 variance 25 Standard Deviation is the square root of standard deviation = square root of va standard deviation = square root(25) z-score =
- Scores on a certain exam are normally distributed with a mean of 90 and a variance of 25. What is th z value St Dev mean 90 5 variance 25 LESS Than GREATER Than
- Which one of the following is not a characteristic of a normal distribution?
- If the z-value of a given x value is positive, it means that
- Assume a normal distribution and find the following probabilities. LESS Than GREATER Than X is normally distributed with mean 50 and standard deviation 4, what is P(45 < X < 58)?
P(X < x) x Precise answer 0.022750^80 x P(X > x) 22 1. P(X < x) x Precise answer 0.0000^25 x P(X > x) 85 0.
x1 (x1 < X < x 19.74917289 5% x P( > x) 12.1601441 98% P( < x) x 75% 22. a. At what operating cost would only 23% of the operating costs be less? b. At what operating cost would 65% of the operating costs be more? c. What operating cost would be more than 85% of operating costs? Precise answer 2276207 Mean 70940 St Dev LESS Than GREATER Than
- Suppose X is normally distributed with mean 20 and standard deviation 4, find the value x0 such that Inverse Calculations
- According to the Air Transport Association of America, the average operating cost of an MD-80 jet air Inverse Calculations P( < x) x 85% 2265. x1 (x1 < X < x 1839.40 85% a. probability =P(Z>-6.46) = 1 b. probability=P(Z<-9.33) = 0 Z-Calculator z=(x-μ)/σ z = x mean = μ std dev = σ 1614000 2276207 70940 -9.
- Selection of the winning numbers is a lottery is an example of.
- A type of random sampling in which every kth item (where k is some number) in the population is s
- Suppose samples of size 100 are drawn randomly from a population that has a mean of 20 and a st
- In a recent year, the average daily circulation of the Wall Street Journal was 2,276,207. Suppose the s a. On what percentage of days would circulation pass 1,818,000? b. Suppose the paper cannot support the fixed expenses of a full-production setup if the circulation Mean StDev 20 4 Mean StDev 2087 172 x P( > x) 1908.73 85% P(X < x) x 0.0000 25 x P(X > x) 85 0.
- The Aluminum Association reports that the average American uses 56.8 pounds of aluminum in a ye households is monitored for one year to determine aluminum usage. If the population standard deviatio pounds, what is the probability that the sample mean will be each of the following? Z Score 1 Minus (^) Z-Table of Z S a. More than 60 pounds 60 1.87 1 - 0. b. More than 56 pounds 56 -0.47 1 - 0. c. Between 55 and 57 pounds 55 -1.05 1 - 0. 57 0.12 1 - 0. d. Less than 54 pounds 54 -1.64 No Subtraction for less tha 0. e. Less than 47 pounds 47 -5.73 exceed z table = 0 Normal Distribution (^) Sample Distribution x Probability Calculations StDev n
x
of Random
New StDev Mean StDev 56.8 1.
50
Precise answer
- The U.S. Bureau of Labor Statistics released hourly wage figures for various countries for workers in The hourly wage was $30.67 for Switzerland, $20.20 for Japan, and $23.82 for the U.S. Assume that in a deviation of hourly labor rates is $4.00. a. Suppose 44 manufacturing workers are selected randomly from across Switzerland and asked what t probability that the sample average will be between $30.00 and $31.00? b. Suppose 34 manufacturing workers are selected randomly from across Japan. What is the probability exceed $21.00? c. Suppose 48 manufacturing workers are selected randomly from across the United States. What is the average will be less than $22.85? Z-Table of Z Score Switzerlan $ 30.67 30 -1.11 0. 31 0.55 0.7088 0. Japan $ 20.20 21 1.33 0.879 0. US $ 23.82 22.85 -1.61 0.0465 No Subtraction for less tha StDev 4 mean $ 24. Normal Distribution Sample Distribution x Probability Calculations Precise answer StDev n
x
of Random
New StDev Mean StDev $ 24.90 0. 4 44
P(X < x) x 1.0000 (^54) x P(X > x) 21 1. P(X < x) x 0.0509 (^54) x P(X > x) 60 0.
In Between x1 (x1 < X < x x 45 0.8716^58 P(X ≥ x0) = 0.975. 12. x
liner is $2,087 per hour. Suppose the operating costs of an MD-80 jet airliner are normally distributed **1959.
2265.** x
tandard deviation is 70,940. Assume the paper’s daily circulation is normally distributed. 1 everyday it circulation is higher than s below 1,614,000. If the probabil 0 ten will this even happen, based on this historical information? random sampling elected for inclusion in the sampl systematic sampling andard deviation of 5. What is the 0.
andard deviation of 5. What are t 20 and. andard deviation of 5. What is the 0. 56
ter/Novelli showed that how a company handles a crisis nce. Quality of product was the number one influence, om aken and each is asked which of these three factors influence their buying decisions. Approximately how many people should he sample from each stratum? en at fault is an influence in their buying decisions? in their buying decisions? complaints is an influence in their buying decisions?
ill be sqrt(np(1-p)). score of -1.8519. p(-2.7778 < z < -1.8519) = 0.
x 1 P(x 1 < X < x 2 ) x 2 55 0.4001^57 the manufacturing sector. ll three countries, the standard heir hourly wage is. What is the that the sample average will probability that the sample n Sample x 1 P(x 1 < X < x 2 ) x 2 30 0.0000^31
