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    Normal Distribution

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    Normal (z) Distributions- In grading Oranges into "A","B" and "C", a large orchard uses weights to distinguish Oranges. If the day's pick shows 16.6% are grade "A" and 6.68% are grade "C", determine the Mean and Standard Deviation.

    In grading Oranges into "A","B" and "C", a large orchard uses weights to distinguish Oranges. Any Orange weighing more than 2 ounces is classified as grade "A", while an Orange weighing less than 0.75 ounces is classified as grade "C". If the day's pick shows 16.6% are grade "A" and 6.68% are grade "C", determine the Mean and St

    statistical test experiments

    Im working on an experiment for my A level course (UK) that will determine the effects of different respiratory substrates on yeast population growth. Im using 4 sugars; fructose, glucose, sucrose and lactose. Using a haemocytometer I'll find the size of the yeast population before the sugar is added and the growth 1 week afte

    Data rejection following normality tests

    Using the Anderson-Darling test for Normality it has been determined that three sets of data "RelHum" (Relative Humidity), "Rain" (Average Rainfall), and "SO2Pot", (SO2 Pollution Potential) all FAIL the test even following log and square root transformation. How do I reject data points in order to make these data sets normal

    Computation

    Please see the attached file for full problem description.

    Normal distribution

    These are questions from a past paper that Iam lost with. Can you do each question in a way that is broken down into simple steps leading to the answer. It is important to me that each step is shown clearly. please help im fed up of this battle with stats. 1)IQ of people normally distributed with mean 120 and standard devi

    Acceptance-sampling scheme

    Consider an acceptance-sampling scheme in which a factory takes delivery of a batch of components if a random sample of 400 components contains fewer than M defectives. Otherwise the batch is returned tot he supplier. Suppose the factory manager wants to set M so that there is no more than a 10% risk of accepting a batch that

    Mean and variance

    7) suppose the average weight of an item labeled 16 ounces actually has mean 17 ounces and variance 4 (ounce^2). What is the approximate probability that the combined weight of 25 items exceeds 445 ounces? What theorem is useful in answering this question?

    Normal and Standard Distribution

    A very large number of fish are swimming in a lake. Their weights are normally distributed with mean 1.30kg and a standard deviation 0.40kg. Fish caught with weights less than 0.5kg have to be thrown back. a) If an angler catches a randomly selected fish, what is the probability that the fish has to be thrown back? b) find

    Explaining Normal Distribution

    I was wondering if someone could help explain the Normal Distribution to me, maybe in more simple terms. An example would also be useful. I am using the program Minitab to generate my answers to questions.

    Normal Distribution Functions Solved

    A university professor keeps records of his travel time while he is driving between his home and the university. Over a long period of time he has found that his morning travel times are approx Normally distributed with a mean of 31 minutes and a standard deviation of 3.0 minutes;his return journey in the evening is similarly d

    Joint Distributions (Normal Distributions)

    Tim has two more problems to solve on his test, but he doesn't know how long it will take to finish them. He assigns mutually irrelevant normal distributions to the times, assigning a mean of 35 minutes to the first problem and 30 minutes to the second problem. He assigns a 95% chance that the first problem will take 35+-15 minu

    Probability: Systolic Blood Pressure

    Assume that the mean systolic blood pressure of normal adults is 120 millimeters of mercury (mm Hg) and the standard deviation is 5.6. Assume the variable is normally distributed. A.) If an individual is selected at random, find the probability that the person's pressure will be between 118 and 121.8mm Hg. B.) If a sample

    Determine bounds by the normal distribution table

    The average weight of an airline passenger's suitcase is 45 pounds. The standard deviation is 2 pounds. If 15% of the suitcases are overweight, find the maximum weight allowed by the airline. Assume the variable is normally distributed.

    Statistics problem

    The director of emergency medicine at NYU hospital is studying patient waiting times. "waiting time" is defined as the time from when a patient enters the facility until he or she is seen by a physician. The study indicates that waiting time follows a normal distribution with a mean of 22 minutes and a standard deviation of 8 mi

    Normal Distribution and Percentiles

    True or false: It is not possible for the score in a distribution, not necessarily normal, which ranks as the 90th percentile to also be the mode for the distribution.

    Normal Distribution

    In a production run of 40 of a particular model of radiation detector, there are four which have defective circuits. If a sample of three of these is chosen without replacement, what is the probability that all three will be defective?

    Normal distribution, standard deviation and mean

    True or false: When the variable is normally distributed, the sample size is less than 30, and the population standard deviation is known, then the t distribution must be used to find confidence intervals for the mean.

    Normal Distribution Confidence Functions

    VISA reported with 95% confidence that 19% of those surveyed used checks to pay for purchases. If 1478 people participated in the survey, what was the percentage of error?

    Normal Distribution in a Large Sample

    A tornado has blown through a section of Collinsville. The insurance adjuster wants to estimate the average claim to within $500. If the standard deviation is believed to be $1600 and the company wants to be 99% sure of their figures, how large a sample must be taken?

    Normal Distribution and Significance Levels True of False

    True or false: A retailer wants to estimate with 99% confidence the number of people who buy at his store. A previous study showed that 15% of those interviewed had shopped at his store. He wishes to be accurate within 3% of the true proportion. The minimum sample size necessary would be 940.

    Normal distribution, standard deviation and mean

    If IQ scores on a Stanford-Binet Test are normally distributed with a mean of 100 and a standard deviation of 15, then about how many people in a randomly chosen million would be expected to score at 160 or above? (This was at one time the break off score for the "genius" designation.) a) 47 b) 32 c) 16

    Normal Distribution

    #2 If you are grading the class according to your z score in a normal distribution. would you rather have a score of 70 in class A where the mean is 55 and the standard deviation is 10, or a score of 80 in class B where the mean is 60 and standard deviation is 15? What would the percentile rank be in class A and B and what does

    Normal Approximation

    Here is a simple probability model for multiple-choice tests. Suppose that each student has probability p of correctly answering a question chosen at random from a universe of possible questions. (A strong student has a higher p than a weak student.) Answers to different questions are independant. Jodi is a good student for whom