Wednesday

April 16, 2014

April 16, 2014

Number of results: 33,959

**Statistics: Sample Size, Variance and Standard Dev**

Sample Size, Variance and Standard Deviation A student organization plans to ask 100 randomly selected students how much they spent on textbooks last semester. You argue for a sample of 900 students instead of 100. You know the standard deviation of the sample mean x of the ...
*Tuesday, September 11, 2007 at 4:26pm by Carma*

**statistics**

Steps to calculate the variance version of standard error: 1. Square the standard error. 2. Multiply the square of the standard error by the sample size. The result should be the variance of the sample.
*Wednesday, September 26, 2012 at 8:51pm by MathGuru*

**Statistics**

The variance of the population is 100. variance sample= populationvariance/n* = 100/2=50 sample standard deviation: sqrt 50 or 7.07 This is widely used, however it is very "flaky" data. A better estimate is to put n-1 in the denominator, but anyone sampling with a sample of ...
*Friday, May 7, 2010 at 5:49pm by bobpursley*

**Statistics**

Suppose that the fit to the simple linear regression of Y on X from 6 observations produces the following residuals: -3.3, 2.1, -4.0, -1.5, 5.1, 1.6. a) What is the estimate of sigma squared? b) What is the estimate of sigma? c) What are the degrees of freedom? Sigma = ...
*Wednesday, March 14, 2007 at 7:39pm by MMK*

**Statistics**

two samples of data regarding salary of Co A and Co B determine if you can be 99% sure that Co? A makes more than Co B? Company A - Mean 55,000, Std Dev 5,000, Sample Size 200; Co B mean 52,000, Std Dev 3,000 Sample size 400 please show steps thanks
*Monday, April 23, 2012 at 8:28pm by stylists*

**Statistics**

Are these statements true or false? 1. The sample mean, the sample proportion and the sample standard deviation are all unbiased estimators of the corresponding population parameters. 2. If the population is normally distributed with known variance then the sample mean may not...
*Friday, November 5, 2010 at 5:03pm by help*

**statistics**

I recommend using your calculator. I calculated sigma(n-1) as a sample, and got 4.705, making variance(sample)=22.14 You may not be wanting sample standard deviation and variance. Use your calculator.
*Tuesday, February 9, 2010 at 9:10pm by bobpursley*

**elementary statistics**

There are different ways you can do this kind of problem, but the formula below might be one of the easier ways: s/[1 + (1.645/√2n)] ..to.. s/[1 - (1.645/√2n)] ...where s = standard deviation, 1.645 represents the 90% confidence interval using a z-table, and n = ...
*Saturday, November 30, 2013 at 7:44pm by MathGuru*

**Research and Statistics**

What factors influence the size of the t-statistics( mean difference, variance, sample size) and which way?
*Monday, February 10, 2014 at 1:47pm by Erica*

**Statistics**

Need step by step format can't figure out, need an example: two samples of data regarding salary of Co A and Co B determine if you can be 99% sure that Co? A makes more than Co B? Company A - Mean 55,000, Std Dev 5,000, Sample Size 200; Co B mean 52,000, Std Dev 3,000 Sample ...
*Saturday, April 21, 2012 at 5:13pm by stylists*

**Statistics**

Need step by step format can't figure out, need an example: two samples of data regarding salary of Co A and Co B determine if you can be 99% sure that Co? A makes more than Co B? Company A - Mean 55,000, Std Dev 5,000, Sample Size 200; Co B mean 52,000, Std Dev 3,000 Sample ...
*Saturday, April 21, 2012 at 5:13pm by stylists*

**Statistics**

A normal population has an expected value of 60 and a variance of 30. Use the central limit theorem to determine what the sample size should be such that the mean has a probability of 90% to fall between the values 58 and 62. One concept of the Central Limit Theorem is ...
*Thursday, August 10, 2006 at 2:06am by ruth*

**statistics**

hint: what does small sample size tell you about the standard deviation or variance (is it small or large?)?
*Tuesday, August 2, 2011 at 10:51pm by TutorCat*

**Statistics**

SAT scores are normally distributed with a mean of 500 and a standard deviation of 100. Using the formula for σM, what will σM be when a. the sample size is 25 b. the sample size is 121, and c. the sample size is 400?
*Monday, November 18, 2013 at 8:04pm by Mikos*

**statistics**

The standard error of the mean (SEM) is a measure of how well the sample mean is estimated - so if you increase the sample size, the standard error of the mean should get smaller. Specifically, if S is the standard deviation of the sample, then the SEM = S/sqrt(N), where N is ...
*Saturday, October 6, 2012 at 3:12pm by David Q/R*

**statistics**

Your data: Sample 1 Sample size = 60 Variance = 121 (variance is standard deviation squared) df = n - 1 = 59 (df = degrees of freedom) Sample 2 Sample size = 120 Variance = 289 df = n - 1 = 119 Determine your test statistic from the appropriate formula using variance. Critical...
*Thursday, May 6, 2010 at 1:52pm by MathGuru*

**Quantitative Analysis**

The "standard deviation of the sample score" divided by the "square root of the sample size" is the formula for computing the ...? A. Coefficiant of Determination B. Absolute Deviation C. Variance D. Standard Error
*Wednesday, November 6, 2013 at 3:14pm by Stacie*

**statistics**

Assuming that the population variances are equal for Male and Female GPAs, test the following sample data to see if Male and Female PhD candidate GPAs (Means) are equal. Conduct a two-tail hypothesis test at =.01 to determine whether the sample means are different. Do NOT ...
*Wednesday, October 6, 2010 at 9:37am by Anonymous*

**statistics**

Lets assume you have taken 100 samples of size 36 each from a normally distributed population. Calculate the standard deviation of the sample means if the populations variance is 25.
*Sunday, June 13, 2010 at 6:30pm by Anonymous*

**statistics**

Z-statistic = (sample mean - population mean)/(standard deviation/square root of sample size) sample mean = 105 population mean = 100 standard deviation = 15 sample size = 75 I'll let you take it from here to calculate.
*Saturday, March 30, 2013 at 7:49pm by MathGuru*

**statistics**

Null and alternative hypotheses: Ho: The population standard deviation is = 7.0 Ha: The population standard deviation is > 7.0 Data given: sample standard deviation = 7.6 level of significance = 0.10 n = 26 The test statistic used in making a decision is the chi-square. ...
*Saturday, July 28, 2012 at 1:40pm by MathGuru*

**statistics**

a population has a mean of 1100 an st. dev of 15. ind the mean and st.dev of the sample mean with the given size : a) n- 50 b)n = 50
*Thursday, May 12, 2011 at 7:20pm by louanee*

**statistics**

a population has a mean of 1100 an st. dev of 15. ind the mean and st.dev of the sample mean with the given size : a) n- 50 b)n = 50
*Thursday, May 12, 2011 at 7:20pm by louanee*

**statistics**

For your first problem: Standard Deviation = 3.29 (Standard deviation is the square root of the variance) Variance = 10.82 (Variance is standard deviation squared) Using a chi-square table for the endpoints: (n-1)s^2/16 to (n-1)s^2/1.69 (8-1)10.82/16 to (8-1)10.82/1.69 7(10.82...
*Monday, March 18, 2013 at 12:32am by MathGuru*

**Statistics**

An IQ test is designed so that the mean is 100 and the standard deviation is 19 for the population of normal adults. Find the sample size necessary to estimate the mean IQ score of statistics students such that it can be said with 95% confidence that the sample mean is within ...
*Wednesday, February 12, 2014 at 10:12pm by Stephanie*

**statistics**

You want to determine if your widgets from machine 1 are the same as machine 2. Machine 1 has a sample mean of 5 and a population standard deviation 1 and a sample size of 4. Machine 2 has a sample mean of 8 and a population standard deviation of 2 with a sample size of 4. ...
*Monday, October 11, 2010 at 10:39pm by Anonymous*

**Statistics**

Using the z-test formula, solve for sample mean: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Find z in a z-table using p-value. Population mean is 48. Standard deviation is 3.5 and sample size is 75. I'll let you take...
*Wednesday, March 23, 2011 at 9:48pm by MathGuru*

**Stats**

A simple random sample will be obtained from a normally distributed population. Find the minimum sample size needed to be 99% confident that the sample standard deviation s is within 5% of the standard deviation. Is such a sample size practical in most cases? The minimum ...
*Monday, November 28, 2011 at 9:50pm by Lindsey*

**statistics**

IQ scores are normally distributed with a mean of 105 and a standard deviation of 18. Assume that many samples of size n are taken form a large population of people and the mean IQ score is computed for each sample. If the sample size is n=64, find the mean and standard ...
*Thursday, September 13, 2012 at 3:51pm by kimberly*

**Math Statistics**

In general, what is the relationship between the standard deviation and variance? a. Standard deviation equals the squared variance. b. Variance is the square root of standard deviation. c. Standard deviation is the square root of variance. d. These two measures are unrelated.
*Saturday, September 29, 2012 at 6:41pm by Misty*

**Statistics**

Remember that standard deviation is the square root of the variance. Formula: t = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) t = (22.10 - 17.10)/(6.7082/√10) I'll let you finish the calculation. The test is one-...
*Tuesday, February 5, 2013 at 10:20pm by MathGuru*

**statistics**

A researcher is testing a null hypothesis that states: H: = 50. A sample of 25 scores is selected and the mean is M = 55.Assuming that the sample variance is s2 = 100, compute the estimated standard error and the t statistic. Is this sample sufficient to reject the null ...
*Friday, April 15, 2011 at 7:57pm by kesha*

**Statistics**

If you perform a statistical test, try a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Population mean = 80 Sample mean = ? (I don't see one listed) Standard deviation = 10.15 Sample size = 50 Once you...
*Monday, November 25, 2013 at 5:22pm by MathGuru*

**statistics**

what are the mean and standard deviation of a sampling distribution consisting of samples of size 16? these sameples were drawn from a population whose mean is 25 and who standard deviation is 5. a. 25 and 1.25 b. 5 and 5 c. 25 and 5 d. 5 and 1.25 e. 25 and square root of 5 ...
*Sunday, February 1, 2009 at 9:37pm by helga*

**Statistics**

This appears to be a hypothesis test involving inferences concerning two variances (standard deviation is the square root of the variance). Sample 1: n = 25; variance = sd^2; df = n - 1 = 24 Sample 2: n = 25; variance = sd^2; df = n - 1 = 24 Note: sd = standard deviation. Test...
*Thursday, June 19, 2008 at 5:22am by MathGuru*

**statistics**

A psychologist wants to estimate the variance of employee test scores. A random sample of 18 scores had a sample standard deviation 10.4. Find a 90% confidence 2 interval for the population variance. What assumption, if any, have you made in calculating this interval estimate?
*Wednesday, November 9, 2011 at 9:21am by Janelle*

**statistics**

A random sample of n=16 scores is obtained from a population with a mean of = 80 and a treatment is administered to the sample. After treatment, the sample mean is found to be M=82. a)Assuming the sample contained n=16 individuals, measure the size of the treatment effect by ...
*Wednesday, March 5, 2008 at 12:30am by Laurie*

**statistics**

if a sample of a distribution of sample size 26 has a range of 56, then what would be an estimate of the sample standard deviation
*Thursday, February 14, 2013 at 1:02pm by karen*

**sample size/ standard deviations**

How do we compute sample size fluctuations? Suppose we have a population of 16000 and a sample size of 30, and the number of samples 1000, what will be the impact on population mean and standard deviation when the population is normally distributed? When the population is ...
*Thursday, December 1, 2011 at 10:15am by ut*

**Statistics**

Use a x squared-test to test the claim about the population variance or standard deviation at the given level of significance and using the given sample statistics. Claim: ơ2 ≤ 60; α = 0.025. Sample statistics: s2 = 72.7, n = 15
*Wednesday, December 26, 2007 at 5:00pm by Brandon*

**Math**

You want to estimate the mean amount spent by customers at a local gas station with 98% confidence and a margin of error of no more than $2. Preliminary data suggests that the standard dev. is $5.1 is a reasonable estimate for the standard dev. for all customers. How large a ...
*Saturday, February 19, 2011 at 9:11pm by Leah*

**Statistics**

Use a chi-squared test to test the claim about the population variance or standard deviation at the given level of significance and using the given sample statistics. Claim: ơ2 ≤ 60; α = 0.025. Sample statistics: s2 = 72.7, n = 15
*Thursday, December 27, 2007 at 11:37am by Brandon*

**STATISTICS**

WHAT DOES THE CENTRAL LIMIT THEOREM SAY ABOUT THE TRADITIONAL SAMPLE SIZE THAT SEPARATES A LARGE SAMPLE SIZE FROM A SMALL SAMPLE SIZE?
*Thursday, July 18, 2013 at 9:35pm by LINDA*

**statistics**

Suppose we take a random sample of size n from a normal population with variance, σ2 . It can be shown that (n−1)s2/σ2 has a chi-square distribution with n−1 degrees of freedom, where s is the sample variance. Below is a random sample of size 8 drawn from...
*Monday, March 18, 2013 at 12:32am by sandy*

**business statistics**

A random sample of size 15 taken from a normally distributed population reveled a sample mean of 75 and a sample variance of 25. The upper limit of a 95% confidence interval for the population mean would equal?
*Saturday, August 1, 2009 at 11:27am by Samantta*

**Statistics**

Check my answers please! Thanks a lot. Five students reported that the previous night they slept: 7,8,7,10,9 hours. Calculate the sample varience and standard deviation. sample varience = 1346.5 standard deviation = 36.7 Consider this. Ths standard deviation can never be ...
*Thursday, February 1, 2007 at 12:35pm by Jake*

**Statistics**

This is a hypothesis test involving variances. Sample size for paper shredders = 7 Variance = ? (you will need to calculate the variance from the data given) degrees of freedom = 6 (df = n - 1) Sample size for calculators = 7 Variance = ? (you will need to calculate the ...
*Wednesday, November 10, 2010 at 8:20pm by MathGuru*

**Statistics**

I have no idea of the significance of the ones and rectangles of dots. If you want a square root symbol (√), use the (option + v) keys. The standard deviation for a sample is usually indicated with s, but the mean of a population is indicated by (option + m). Subtract ...
*Friday, December 20, 2013 at 7:14pm by PsyDAG*

**statistics**

Here are a few hints to get you started: a). Standard error of the mean = standard deviation divided by the square root of the sample size b). CI95 = mean 1.96(sd/√n) ...where 1.96 represents the 95% interval using a z-table, sd = standard deviation, and n = sample ...
*Tuesday, February 21, 2012 at 4:28pm by MathGuru*

**Statistics**

Suppose that a sample of size 60 is drawn from a population with mean 73 and standard deviation 79. Find the value of , the standard deviation of the distribution of sample means. How do I work this on my calculator?
*Tuesday, June 18, 2013 at 12:09pm by Anonymous*

**statistics**

Determine the 90% confidence interval for a sample, taken from a normally distributed population, that has a mean of 685, a sample standard deviation of 74, and a sample size of 29
*Tuesday, November 1, 2011 at 3:13pm by Tierra*

**statistics**

Determine the 90% confidence interval for a sample, taken from a normally distributed population, that has a mean of 685, a sample standard deviation of 74, and a sample size of 29
*Tuesday, November 1, 2011 at 3:32pm by Tierra*

**STATISTICS**

According to the Central Limit Theorem, The traditional sample size that separates a large sample size from a small sample size is one that is greater than 100 30 500 20
*Thursday, June 10, 2010 at 6:09pm by John*

**statistics**

How do we compute sample size fluctuations? Suppose we have a population of 16000 and a sample size of 30, and the number of samples 1000, what will be the impact on population mean and standard deviation when the population is normally distributed? When the population is ...
*Thursday, December 1, 2011 at 8:19am by Nasir*

**Statistics**

If the population is normally distribution then the sample must be normally distributed even for small sample size? True or False. The variance of the standard normal distribution is always equal to 1.? True or False. A continuous random variable may not be normally ...
*Friday, February 7, 2014 at 4:25pm by Jamie*

**statistic**

. For each of the following, assume that the two samples are selected from populations with equal means and calculate how much difference should be expected, on average, between the two sample means. a. Each sample has n _ 5 scores with s2 _ 38 for the first sample and s2 _ 42...
*Sunday, November 11, 2012 at 8:25pm by Sharon*

**Statistics**

standard error= standard of population/sqrt(sample size)
*Monday, December 20, 2010 at 3:23pm by TutorCat*

**statistics**

How is the standard error of the mean influenced by sample size and standard deviation?
*Saturday, October 6, 2012 at 3:12pm by Nina*

**statistics**

Standard Error = standard deviation divided by the square root of the sample size
*Tuesday, October 4, 2011 at 3:53pm by MathGuru*

**Statistics**

IQ score are normally distributed with a mean of 95 and a standard deviation of 17. If the sample size is n=36 find the mean and standard distribution of sample mean
*Sunday, April 7, 2013 at 2:47pm by Megan*

**math**

A sample of size 100 is taken resulting in a standard deviation of 3. Construct a 95% confidence interval for the population variance.
*Wednesday, May 8, 2013 at 11:28pm by Jewelz*

**Statistics**

find the 90% confidence interval for the variance and standard deviation of a sample of 16 and a standard deviation of 2.1 Assume the variable is normally distributed.
*Sunday, October 24, 2010 at 10:56pm by Anon*

**Stats.**

Null and alternative hypotheses: Ho: The population standard deviation is = 505.6 Ha: The population standard deviation is > 505.6 Data given: sample standard deviation = 840 (Note: standard deviation is the square root of the variance; therefore, variance is standard ...
*Monday, March 28, 2011 at 11:43am by MathGuru*

**statistics**

Standard error of the mean = standard deviation divided by the square root of the sample size
*Wednesday, August 25, 2010 at 2:12pm by MathGuru*

**statistics**

Standard error of the mean: Standard deviation divided by the square root of the sample size.
*Monday, June 18, 2012 at 4:51pm by MathGuru*

**Statistics**

For sample mean x = 150, sample size n = 36 and sample standard deviation s = 40 find 80% confidence interval for population mean. Population standard deviation is not known
*Friday, February 24, 2012 at 2:13pm by Tina*

**STAT**

You want to determine if your widgets from machine 1 are the same as machine 2. Machine 1 has a sample mean of 15 and a sample standard deviation 6 and a sample size of 18. Machine 2 has a sample mean of 12 and a sample standard deviation of 6 with a sample size of 18. With an...
*Friday, October 4, 2013 at 5:07pm by Tammy*

**statistics**

a simple random sample will be obtained from a normally distributed population. find the minimum sample size needed to be 95% confident that the sample standard deviation (s) is within 10% of sigma. please help!
*Saturday, April 16, 2011 at 12:03pm by lucy*

**Sampling Distribution**

Sampling Distribution Complete solutions and illustrations are required. 5.The standard deviation of a variable is 15. If a sample of 100 individuals are selected compute for a.The standard error of the mean. b.What sample size is necessary to double the standard error of the ...
*Wednesday, February 27, 2013 at 10:55pm by Tina*

**statistics**

You have to find the z-score for .03 from a table. Substitute it below to solve for standard dev. z-score = (39.2 - 58)/stand.dev.
*Monday, March 4, 2013 at 1:39pm by Dr. Jane*

**statistics**

A population has a mean =80 and a standard deviation =8. find the mean and standard deviation of a sampling distribution of sample means with sample size=64
*Tuesday, February 12, 2013 at 10:39am by antorio*

**statistics**

Formula for one-sample z-test statistic: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) I'll let you take it from here.
*Tuesday, October 16, 2012 at 8:12pm by MathGuru*

**stat**

Null and alternative hypotheses: Ho: The population standard deviation is = 15 Ha: The population standard deviation is < 15 Data given: sample standard deviation = ? (Note: standard deviation is the square root of the variance; therefore, variance is standard deviation ...
*Monday, May 14, 2012 at 9:33am by MathGuru*

**Statistics**

Standard error of the mean is the standard deviation of the sampling distribution of the means. Take the standard deviation (15) and divide by the square root of the sample size (100) for your answer.
*Sunday, October 14, 2012 at 9:41pm by MathGuru*

**Statistics**

There are 200 students in a sample. How many of these students will have scores that fall under the score of 41? Mean is 45, standard dev. is 4.
*Tuesday, November 15, 2011 at 9:16pm by Vicki*

**statistics**

sigma is the standard deviation of a population of size N S is the standard deviation of a sample of size n from within the population. What is the estimated value of S^2? If the population was infinitely large (size N = infinity), what would the estimated value of S^2 be?
*Thursday, February 21, 2008 at 5:25pm by mathstudent*

**Statistics**

Try a t-test since your sample size is rather small. Formula: t = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) sample mean = 8.2 population mean = 7.3 standard deviation = 1.4 sample size = 20 Plug in the values and ...
*Sunday, March 10, 2013 at 1:30pm by MathGuru*

**statistics**

As far as I know (statistics is not really my specialty), the sigma of the sample depends only on the sample size, not the size of the population the sample is chosen from. Therefore in my ignorance I would say: S^2 sample = sigma^2 of population / n or sigma sample = sigma ...
*Thursday, February 21, 2008 at 5:25pm by Damon*

**Statistics- I think I have the answer**

Your pick is incorrect. It's either c) or d). Remember that standard deviation is the square root of the variance, and variance is standard deviation squared.
*Sunday, March 29, 2009 at 4:49pm by MathGuru*

**statistics**

Let X be the average of a sample of size 25 independent normal random variables with mean 0 and variance 1. P[[X<c]=0.5 (a) Determine c such that (b) Now assume that the observations may not be normally distributed, but they still are independent with mean 0 and variance 1...
*Wednesday, November 23, 2011 at 11:17am by zwesko*

**statistics **

Info given:With a random sample of 9 men. let X denote the number of men with head circumference larger than 57.8cm. the normal mean=56cm and standard dev=1.8cm. So this is a binomal dis- they ask; For X, calculate pr(X=2)? second part, Let X denote the number of men with HC ...
*Thursday, April 15, 2010 at 3:30am by UPD*

**statistics**

Given a sample size of 38, with sample mean 660.3 and sample standard deviation 95.9 we are to perform the following hypothesis test. Null Hypothesis H0: = 700 Alternative Hypothesis H0: 700 At significance level 0.05 3. Calculate the test statistics (Tip: this is the...
*Monday, August 9, 2010 at 5:05pm by Scott*

**statistics 251**

how do i find the standard deviation and sample variance for $7448, $4911, $9051, $6374, $4227
*Thursday, September 13, 2012 at 6:21pm by amirah*

**statistics**

Calculate the variance version of standard error for each sample in Exercise 10.18for the liberals (2, 1, 3, 2) and then for the conservatives (4, 3, 3, 5, 2, 4).
*Wednesday, September 26, 2012 at 8:51pm by susan*

**statistics**

Try a t-test since your sample size is rather small. Formula: t = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) sample mean = 12 population mean = 10 standard deviation = 3 sample size = 26 Plug in the values and calculate ...
*Tuesday, May 3, 2011 at 11:11pm by MathGuru*

**Statistics**

You are getting ready to take a sample from a large population, and need to determine the appropriate sample size. You are estimating sales at a large chain of department stores. A previous survey from the same population found a standard deviation of $18. What sample size is ...
*Monday, July 16, 2012 at 12:29pm by Devika*

**Statistics**

Standard error of mean = Standard deviation/√(n-1) SD^2 = Variance Variance of mean = 4.4/19 = ?
*Monday, August 2, 2010 at 12:00am by PsyDAG*

**statistics**

The weights (in pounds) of a sample of five boxes being sent by UPS are: 12, 6, 7, 3, and 10. a. Compute the mean for this sample. Show your work!! b. Compute the range for this sample. Show your work!! c. Compute the variance for this sample. Show your work!! d. Compute the ...
*Saturday, February 14, 2009 at 1:18am by DJ*

**statistics**

For normal population mean 60, standard deviation 15, after treatment is given to the member of sample , the sample mean is 65, and sample size is 25. is the sample mean sufficient to conclude that the treatment has significant effect? Give reason for decision?
*Saturday, August 11, 2012 at 11:38pm by Anonymous*

**STATISTICS**

Since your sample size is small and the problem doesn't say that the population has a normal distribution, you may want to use a t-table to determine the 95% confidence interval. A general example of a formula is: CI95 = mean + or - (t-value)(sd/√n) Note: sd = standard ...
*Thursday, October 11, 2007 at 7:26pm by MathGuru*

**STAT**

You want to determine if your widgets from machine 1 are the same as machine 2. Machine 1 has a sample mean of 5 and a population standard deviation 2 and a sample size of 4. Machine 2 has a sample mean of 10 and a population standard deviation of 2 with a sample size of 64. ...
*Monday, October 7, 2013 at 1:43pm by Tammy*

**statistics**

The standard deviation of the sampling distribution of the mean is called the standard error of the mean. I'm assuming that is what you wish to calculate. If so, determine the standard deviation and divide by the square root of the sample size.
*Tuesday, June 19, 2012 at 4:53pm by MathGuru*

**statistics**

1. A random sample of size 49 is taken from a large population, measuring the time it takes to complete a drivers license examination. The sample mean was found to be 47 minutes, and the sample standard deviation 5.89 minutes. Construct a 95% confidence interval around the ...
*Friday, July 16, 2010 at 2:53pm by Anonymous*

**statistics**

A random sample of size 81 is taken from a large population, measuring the time it takes to complete a drivers license examination. The sample mean was found to be 43 minutes, and the sample standard deviation 5.71 minutes. Construct a 95% confidence interval around the ...
*Monday, July 16, 2012 at 12:27pm by Devika*

**Statistics**

Kind attention Psydag: A random sample of size 20 from a normal population with sample mean 42 and sample standard deviation of 6 . To test the hypothesis the population mean 44 at 5% level of significance , find the p-value and comment Clarification: The sample size is 20 ...
*Friday, January 1, 2010 at 8:37am by Mrs. Lakshmi*

**Business Statistics**

The standard deviation of all possible sample proportions increases as the sample size increases - TRUE OR FALSE
*Monday, July 11, 2011 at 7:47pm by CS*

**statistics**

A 95% confidence interval for a population mean was reported to be 23,100 to 24,900. If the sample standard deviation is 5,808.26, what sample size was used in this study?
*Sunday, June 5, 2011 at 1:25pm by Anige*

**Statistics**

A 82% confidence interval for a sampling distribution with a mean of 100, a sample standard deviation of 24 and a sample size of 36 will be based on a = ______ and a corresponding Z of ___
*Monday, March 5, 2012 at 3:48am by Jeff*

**Statistics**

A 82% confidence interval for a sampling distribution with a mean of 100, a sample standard deviation of 24 and a sample size of 36 will be based on a = ______ and a corresponding Z of ___
*Monday, March 5, 2012 at 3:49am by Jeff*

**Statistics**

If you have the formula for the variance, standard deviation is the square root of the variance.
*Saturday, February 25, 2012 at 5:45am by MathGuru*

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