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    Normal Distribution

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    Standard distribution, deviation, etc.

    15. If P(A) = 0.4, P(B| A) = 0.35, P(A  B) =0.69, then P(B) = a. 0.14 b. 0.43 c. 0.75 d. 0.59 18. If X and Y are mutually exclusive events with P(X) = 0.295, P(Y) = 0.32, then P(XY) = a. 0.0944 b. 0.6150 c. 1.0000 d. 0.0000 27. For a standard normal distribution, the probability of z  0 is

    The Crossett Trucking Company

    The Crossett Trucking Company claims that the mean weight of their delivery trucks when they are fully loaded is 6,000 pounds and the standard deviation is 150 pounds. Assume that the population follows the normal distribution. Forty trucks are randomly selected and weighed. Within what limits will 95 percent of the sample means

    Normal distribution and Standard Error of the Mean

    5. A professor at a local university noted that the grades of her students were normally distributed with a mean of 73 and a standard deviation of 11. a. The professor has informed us that 7.93 percent of her students received grades of A. What is the minimum score needed to receive a grade of A? b. Students who made 57.93 or

    Test taking validity

    Test Taking When taking a multiple choice test, the old adage comes to mind: 'When in doubt, Pick C'. It turns out that this is true in many cases. On a multiple choice test, with four solutions, the middle two choices tend to be the most correct answers. This presents a Gaussian (normal) distribution for the choices A,

    Sampling Distribution, Mean and Standard Deviation

    See attachment for better symbol representation. 1) A manufacturer of paper used for packaging requires a minimum strength of 20 pounds per square inch. To check on the quality of the paper, a random sample of 10 pieces of paper is selected each hour from the previous hour's production and a strength measurement is recorded

    7 Elementary Statistics Problems - dice probability and normal distribution

    Problems must be worked out so that the average first year college student can understand them. 1. If a gambler rolls two dice and gets a sum of 10. he wins $10, and if he gets a sum of three, he wins$20. The cost to play is $5. What is the expectation of this game? 2. A recent study found that the average life expectan

    Normal probability distribution..

    Birth weights of babies born to full-term pregnancies follow roughly a normal distribution. At Meadowbrook Hospital, the mean weight of babies born to full-term pregnancies is 7 lbs with a standard deviation of 14 ounces (1 pound = 16 ounces). a. Dr. Watts has 4 deliveries (all for full-term pregnancies) coming up during the

    Probability Problem: Normal Distribution

    The lifetime of interactive computer chips produced by a certain semiconductor manufacturer are normally distributed with parameters μ=1.4x10^6 hours and σ=3x10^5 hours. What is the approximate probability that a batch of 100 chips will contain at least 20 whose lifetimes are less than 1.8x10^6? Please see attachmen

    Problems on sampling, hypothesis testing and confidence interval

    1.Which of the following statements about the sampling distribution of the sample mean is incorrect? a. The sampling distribution of the sample mean is approximately normal whenever the sample size is sufficiently large (n>30). b. The sampling distribution of the sample mean is generated by repeatedly taking samples of size n

    Probability: Standard Deviation, Exponential Distribution and Expected Values

    (8) 1. A manufacturer of electronics products expects that 1% of units fail during the warranty period. A sample of 600 independent units is tracked for warranty performance. a) What is the expected number of failures during the warranty period? b) What is the probability that none fails during the warranty period? c) What is

    Multiple choice questions on Normal Distribution, Time Value of Money

    1.Consider the normal distributions drawn below (with different scales) They both have m = 20 and the area of the shaded region of each is 0.90. Which of the following holds? a. x1 < x2 b. x1 > x2 c. x1 = x2 d. There is not enough information e. x1 >= x2 2.If you deposit $5000 into a fund paying 6% interest compou

    Probability using normal distribution.

    H.) The length of time it takes a student to find a parking spot on campus follows normal distribution of mean, 3.5 minutes. The probability that a student will find a spot in less than 3 minutes is: 1.) 0.8085 2.) 0.1915 3.) 0.3085 4.) 0.6915

    Case Study using normal distribution

    A company supplies pins in bulk to a customer. The company uses an automatic lathe to produce the pins. Due to many causes - vibration, temperature, wear and tear, and the like - the lengths of the pins made by the machine are normally distributed with a mean of 1.012 inches and a standard deviation of 0.018 inch. The custome

    Significance Testing Format

    The most important material reclaimed from beverage bottles is PET plastic. A serious impurity is aluminum, which later can clog the filters in extruders when the recycled material is used. The following are the amounts (in ppm by weight of aluminum) found in bihourly samples of PET recovered at the plant over roughly a two day

    Binomial Distribution Chance of Snow

    The number of days per year that it snows in an eastern Idaho town is normally distributed with a mean of 25 days and a standard deviation of 5.4 days. 1. What is the chance that it snows exactly 25 days?

    Standard Normal Distribution Table

    Use the Normal Table to find the following: a) Probability (z < -2.65) b) Probability (z > -1.55) c) Probability (-2.00 < z < 2.25) d) Probability ( 1.25 < z < 2.40) Please show the steps you used to get to the answers.

    Find Percentiles from a Given Normal Distribution

    Your firm is attempting to reduce its cost of maintenance of customers by culling the least-productive of them. A census of sales records was undertaken and it was determined that the mean level of sale of all customers was $235,000 with a standard deviation of $15,000. (a) It is your desire to eliminate from your customer po

    Statistics: Normal Distribution

    *Please see attachment for case study. Questions: (a) What are the observational units and variable units of interest in this study? Also specify the population or process of interest. (b) State and null and an alternative hypothesis about the value of pi (in words and symbols) (c) We can assess the strength of evide

    Z-Scores from Area Size

    6.38 Obtain the z-score that has an area of .95 to its right. 6.40 Find the following z-scores a. z0.03 b. z0.005

    Normal distribution

    6.12 a. The area under the standard normal curve with parameters m = 64.4 and o= 2.4 that lies to the left of 61 is 0.0783. Use this information to estimate the percentage of female's students who are shorter than 61 inches. 6.14 According to the National Health and Nutrition Examination Survey, the serum (noncellular portio

    Using Excel to make plots of Gaussian distribution

    I am using Analytical Chemistry 7th edition By Skoog, West, Holler, and Crouch. please let me know if any additional info. is needed. There is a sample of the graph in the book Chapter 6 and 7. Using Excel, construct a spreadsheet to make two plots of a Gaussian distribution: 1. relative frequency vs deviation from the mean

    Normal Distribution; Mean; Standard Deviation Functions

    I am having trouble with PART B of this problem. Here is the whole problem: Assume body temperatures are normally distributed with mean of 98.2 and a standard dev. of 0.62 Part A) Assuming a hospital defines a fever as 100 or over, determine the percentage of a normal healthy person considered to have a fever using Z tabl

    Statistics

    Question 1 If a normal distribution of empirical scores is converted to a distribution of z scores: A. The new mean will be zero B. The new standard deviation will be one C. Both A and B D. Neither A and B. Question 2 Milquetoasts gracious statistics professor at Northwestern announced that he would drop th

    Stats 5

    The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, and the standard deviation of the sample was 2.7 minutes. Usi

    Uniform Distribution Variables

    1. X_1,X_2,...,X_n are independent and uniformly distributed on [0,1] a. standardize X_1+X_2+...+x_n b. Give mgf of THE STANDARDIZED (a) sum. 2. Suppose X is normal with mean u and variance sigma^2. P{u<= X <= u + 1.5 sigma}

    Finding percentiles of known normal distributions

    All standard IQ test scores are normally distributed and are set up so that the mean score is 100. However, the standard deviation differs from test to test. For example, the standard deviation on the Otis-Lennon test is 16, while the Cattell's standard deviation is 24. The following are three famous high IQ societies, with t

    Find the Critical Values and Determine the Appropriate Distribution

    Do one of the following as appropriate: a) Find the critical value t (alpha/2) b) Find the critical value z (alpha/2) c) State that neither the normal nor the t distribution applies. Problem: 95%; n= 40; sigma is unknown; population appears to be skewed. (See attachment for complete question and symbols that did not come