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Central Limit Theorem

Finding Confidence Interval and Central Limit Theorem

A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were 3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477 (a) Construct a 90 percent confidence interval for the true mean weight. (b) What sample size would be necessary to est

What is the probability that for a randomly selected customer the service time would exceed 3 minutes? If many samples of 64 were selected, what are mean and standard error of the mean expected to be? What is expected to be the shape of the distribution of sample means? If a random sample of 64 customers is selected, what is the probability that the sample mean would exceed 3 minutes?

The amount of time a bank teller spends with each customer has a population mean = 3.1 minutes and population standard deviation = 0.4 minute. a) What is the probability that for a randomly selected customer the service time would exceed 3 minutes? b) If many samples of 64 were selected, what are mean and standard error of t

Confidence Intervals on Faith Healing

This question is asking for speculation about the possible results of a study if we change the size of the population. It all depends on unknowns such as how representative the 100 adults are of the population. In general, the larger the population the sure we are that it is representative of the population. In a poll of 1

Sampling Methods and the Central Limit Theorem

Information from the American Institute of Insurance indicates the mean amount of life insurance per household in the United States is $110,000. This distribution follows the normal distribution with a standard deviation of $40,000. a. If we select a random sample of 50 households, what is the standard error of the mean? b.

Estimating Population Mean and Distribution

1) A state meat inspector in Iowa has been given the assignment of estimating the mean net weight of packages of ground chuck labeled "3 pounds". Of course he realizes that the weights cannot be precisely 3 pounds. A sample of 36 packages reveals the mean weight to be 3.01 pounds, with a standard deviation of 0.03 pounds. A) Wh

Control Limits for a New Machine

A new machine has just been installed to cut and rough-shape large slugs. The slugs are then transferred to a precision grinder. One of the critical measurements is the outside diameter. The quality control inspector randomly selected five slugs each hour, measured the outside diameter, and recorded the results. The measurements

Sampling Methods and Central Limit Theorem (Please see the attachment)

(Please see the attachment) "Information from the American Institute of Insurance indicates the mean amount of life insurance per household in the United States is $110,000. This distribution follows the normal distribution with a standard deviation of $40,000. " "a. If we select a random sample of 50 hou

Abnormal Observations and Control Limits

(a) List four rules for detecting abnormal (special cause) observations in a control chart. (b) Set up a control limits for an x=400, R=5, and n = 4. (Please see the attached document for proper formatting)

Normal Distribution and Central Limit Theorem

The mean amount purchased by a typical customer at Churchill's Grocery Store is $23.50 with a standard deviation of $5.00. Assume the distribution of amounts purchased follows the normal distribution. For a sample of 50 customers, answer the following questions. a. What is the likelihood the sample mean is at least $25.00? b

Understanding the Central Limit Theorem.

Visit the following Web site Central Limit Theorem Applet and read what is posted: http://www.stat.sc.edu/~west/javahtml/CLT.html You will choose from the pull down menu at the bottom of the page both the number of dice and the number of rolls at a time. When you "click" you will be virtually rolling your dice. Complete t

Central Limit Theorem

Why is the Central Limit Theorem so important to the study of sampling distributions? a. it allows us to disregard the size of the sample selected when the population is not normal b. it allows us to disregard the shape of the samplign distribution when the size of the population is large. c. it allows us to disregard the s

Sampling distibutions, central limit theorem, and probabilities

4. A computer supply house receives a large shipment of floppy disks each week. Past experience has shown that the number of flaws per disk can be described by the following probability distribution: Number of Flaws per Floppy Disk Probability 0 .65 1 .2 2

Central Limit Theorem: understanding the Z Score.

Assume that men's weights are normally distributed with a mean of 172 lbs. and a standard deviation of 29 lbs. I understand that if one man is selected the probability his weight is less than 182 lbs is .6331 However I don't understand if 25 men are randomly selected what is the probability that they have a mean weight les

Determining Probability using Central Limit Theorem

A population is normally distributed, with a mean of 23.45 and a standard deviation of 3.8. What is the probability of each of the following? a) Taking a sample of size 10 and obtaining a sample mean of 22 or more b) Taking a sample of size 4 and getting a sample mean of more than 26.

Quantative Research Methods: Sample Size, Confidence Interval

Question 1: As a sample size approaches infinity, how does the student's t distribution compare to the normal z distribution? When a researcher draws a sample from a normal distribution, what can one conclude about the sample distribution? Explain. Question 2: A mayoral election race is tightly contested. In a random sam

Central Limit Theorem and Population Samples

A normally distributed population has a mean of 40 and a standard deviation of 12. What does the central limit theorem say about the sampling distribution of the mean if samples of size 100 are drawn from this population?

Discussing the Main Points of the Central Limit Theorem for a Mean

Question: Why is population shape of concern when estimating a mean? What does sample size have to do with it? Scenario 1: A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams were as given below: 3.087 3.131 3.241 3.241 3.270 3.353 3.4

State the main points of the Central Limit Theorem for a mean.

Question 5 State the main points of the Central Limit Theorem for a mean. Question 6 Why is population shape of concern when estimating a mean? What does sample size have to do with it? 8.46 A random sample of 10 Tootsie Rolls was taken from a bag. Each piece was weighed on a very accurate scale. The results in grams we

Two questions on Central Limit Theorem - Confidence Level and Sample Size

#1 Answer the following based upon the implications of the Central Limit Theorem (assume sample size larger than 30 when samples are mentioned in (a) and (b) below). a) How does the mean of the sampling distribution of all possible sample means from a population compare to the mean of the population? b) How does the stan

Central Limit Theorem

? Visit the following Web site Central Limit Theorem Applet and read what is posted: http://www.stat.sc.edu/~west/javahtml/CLT.html ? From the pull down menu at the bottom of the page, choose 5 for number of dice. For the number of rolls at a time from that menu, again choose 5. ? Click to roll your virtual dice. Keep trac

Statistics Definitions

What is the sampling distribution of sample means? What is the mean of the sampling distribution of sample means? What is its standard deviation? How is that standard deviation affected by the sample size? What does the central limit theorem state about that distribution?

Normal Distribution Using Central Limit Theorem

The mean weight of newborn babies in a Long Island Community is 7.5 lbs with a standard deviation of 1.4 lbs. What is the probability that a random sample of 49 babies has a sample mean weight of at least 7.2lbs?

Calculation of Mean & Standard Deviation in STATDISK

Using Statdisk 1. Assume all dice have 6 sides, a. simulate the rolling of a single die 800 times (select data than dice generator). Use copy/paste to copy the results to the descriptive statistics and histogram modules, and enter results One Die Mean_____________ Standard Deviation________

SAT Scores and the Central Limit Theorem

Would you be able to baby step walk me through the formulas needed to solve this problem? ie; step 1, step 2, etc. Maybe you could use a similar problem to this one so I can at least understand the process I need to do to get this answer? This book I have does not simplify and step through the method for solving this in a way

Central Limit Theorem Explanation

Explain how the Central Limit Theorem can help you convince your boss that while you can't get rid of sampling error the results from your statistical work (that is based on sampling) can still be useful. HINT: This is more of a story response (i.e. discussion of theory) than a math response (i.e. numbers and calculations flying

Importance of the Central Limit Theorem

Why is the Central Limit Theorem so important to the study of sampling distributions? A. It allows us to disregard the size of the sample selected when the population is not normal B. It allows us to disregard the shape of the sampling distributions when the size of the population is large C. It allows us to disregard

Central limit theorem question

State the Central Limit Theorem The time spent by a factory worker A packing a box is a random variable with mean 3.5 minutes and standard deviation 1 minute. The times spent packing any two boxes are independent. (i) What is the approximate probability that he packs 100 boxes in less than 6 hours? (ii) What is the appr