Tuesday

October 25, 2016
Number of results: 24,770

**Statistics**

How does the standard deviation differ to of the sample mean x bar. Please help I'm confused

*March 2, 2015 by Sam*

**Essentials of statistics**

A populations of scores forms a normal distribution with a mean of 40 and a standard deviation of 12 what is the probability of selecting a sample of n=9 scores with a mean less than m=34

*July 31, 2010 by Anonymous*

**Statistics**

For a sample group of 22, the mean is 86 with a standard deviation of 5. What is the 90% confidence interval of the true mean of the sample? Can you please explain the steps you used to get the answer. Thanks.

*October 24, 2010 by Anon*

**statistics**

a. A random sample of 25 was drawn from a normal distribution with a standard deviation of 5. The sample mean is 80. Determine the 95% confidence interval estimate of the population mean.

*August 15, 2011 by Sally*

**Statistics**

Construct a 95% confidence interval for population mean: My friends measured 40 fish and found that the mean length of the fish sampled was 3.7 cm with a standard deviation of 0.5 cm.

*April 28, 2014 by Mashall*

**Statistics**

A sample of size 16 is taken from a normally distributed population with a mean of 12 and a standard deviation of 3. The probability that the sample mean is equal to 12 is a. 1 b. 0.5 c.-0.5 d.0 please explain

*February 12, 2016 by Sara*

**Stat**

An SRS of size n is taken from a large population whose distribution of income is extremely right-skewed and the mean income is calculated. Which of the following statements is false? a) When n > 30, the sampling distribution of is approximately normal. b) When n increases...

*May 6, 2016 by Sam*

**Math**

I have a problem on standard deviation, and I will need some help with it. Problem: Each professor in an English class give an A to students scoring above 90 and a F to those scoring below 60. Professor 1 has a normal distribution with a mean of 74 and standard deviation 7 ...

*April 12, 2011 by bikie*

**statistics**

worried about customer complaints and potential lawsuits, the manufacterers decided that no more than o.5% of bags of Crunchy corn chips should be underweight. there are 2 possible adjustments that can be made; change the mean setting on the filling machines while leaving the ...

*October 10, 2007 by sophs*

**statistics**

Cholesterol levels of adult males are approximately normally distributed with a mean of mg/dL and a listed standard deviation of . Some researchers claim that the standard deviation of cholesterol levels of adult males is less than . Suppose that we want to carry out a ...

*February 27, 2010 by anaya*

**statistic**

Two samples each of size 25 are taken from independent populations assumed to be normally distributed with equal variances. The first sample has a mean of 35.5 and standard deviation of 3.0 while the second sample has a mean of 33.0 and standard deviation of 4.0. The pooled (i...

*March 17, 2015 by joanne*

**Statistics**

The Tyco Video Game Corporation finds that it is losing income because of slugs used in its video games. The machines must be adjusted to accept coins only if they fall within set limits. In order to set hose limits, the mean weight of quarters in circulation must be estimated...

*July 22, 2015 by Lizzy*

**Math - PreCalc (12th Grade)**

Which statement about a uniform probability distribution defined on a given interval is true? A) The mean is always 0. B) The mean is always 1. C) The standard deviation is always 1. D) The mean is the midpoint of the interval. E) The standard deviation is equal to the width ...

*March 21, 2014 by Shawna*

**statistics**

assuming that you wished to have the highest possible score on an exam relative to ht e other scores, would you rather have a score of 70 on a test with a mean of 60 and a standard deviations of 5.2 or a score of 81 on a test with a mean of 79 and a standard deviation of 7.1?

*July 14, 2014 by nick*

**statistics**

Data from the latest census was analyzed. It was determined that one-parent households spend less on food away from home that do two-parent households. The mean amount spent by 30 one-parent households is $1876 and the standard deviation is $113. The mean amount spent by 30 ...

*April 18, 2012 by Mike*

**statistics**

Jack’s ACT score is 30. Jason’s SAT score is 950. Who did better? The mean SAT score is 1000 with a standard deviation of 100 SAT points. The mean ACT score is 22 with a standard deviation of 3 ACT points

*March 27, 2012 by Chris*

**Statistics**

Assume there are two lakes containing trout and the weights of the trout in each lake are normally distributed. The distribution of trout weight in Lake A has a mean of 18 ounces with a standard deviation of 2 ounces. The distribution of trout weight in Lake B has a mean of 19...

*November 24, 2011 by Brea*

**statistics**

question- a packaging device is set to fill detergent powder packets with a mean weight of 5 kg .the standered deviation is known to be 0.01kg.these are known to drift upward over a period of time due to machine fault,which is not tolerable.a random sample of 100 packets is ...

*October 29, 2010 by sunil*

**Statistics**

New data is added to change the mean time to 6 mninutes and 10 seconds with standared deviation 2 minutes and 5 seconds. The mean depth is now 115.5 feet with standard deviation 31.6 feet. If the association is still negative and r^2=.68, find the slope of the regression line ...

*March 7, 2012 by Shayla *

**university of phoenix**

if someone scored two standard deviations above the mean on a standard test where the mean =100 and the standard deviation = 15, what is the person's numerical score?

*July 13, 2012 by benjamin*

**statistic**

1. A distribution has a standard deviation of 12. Find the z-score for each of the following locations in the distribution. a. Above the mean by 3 points. b. Above the mean by 12 points. c. Below the mean by 24 points. d. Below the mean by 18 points. For the following ...

*January 26, 2013 by Nickie*

**Statistics**

The level of nitrogen oxides (NOX) in the exhaust of a particular car model varies with mean 0.9 grams per mile and standard deviation 0.15 grams per mile . (a) What sample size is needed so that the standard deviation of the sampling distribution is 0.01 grams per mile ?

*January 12, 2012 by Terra *

**Statistics**

he level of nitrogen oxides (NOX) in the exhaust of a particular car model varies with mean 0.7 grams per mile and standard deviation 0.19 grams per mile . (a) What sample size is needed so that the standard deviation of the sampling distribution is 0.01 grams per mile ?

*March 5, 2016 by zoolo*

**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.

*October 24, 2010 by Anon*

**Statistics**

How do you figure this out? For a population that has a standard deviation of 10, what is the standard deviation of the distribution of means for samples of size 2? A-6.33 B-7.07 C-2 D-3.03

*May 7, 2010 by Amanda*

**statistics**

IQ scores distribution of IQ scores is not normally distributed standard with a mean of 100 and a standard deviation of 15, which is represented by a bell-shaped graphical. What is the area under the curve? What is the median? What is the mode?

*April 25, 2015 by norma*

**statistics**

IQ scores distribution of IQ scores is normally distributed standard with a mean of 100 and a standard deviation of 15, which is represented by a bell-shaped graphical. What is the area under the curve? What is the median? What is the mode?

*April 25, 2015 by norma*

**STATISTICS**

IQ scores distribution of IQ scores is normally distributed standard with a mean of 100 and a standard deviation of 15, which is represented by a bell-shaped graphical. What is the area under the curve? What is the median? What is the mode?

*April 25, 2015 by norma*

**Statistics**

What is the mean and standard deviation of 63.7%? What is the mean and standard deviation of 61.4%? Using the 68-95-99.7 rule, describe the sampling distribution of 63.7% Using the 68-95-99.7 rule, describe the sampling distribution of 61.4%? Please help I am so lost...

*October 16, 2013 by Lisa*

**Statistics**

What is the mean and standard deviation of 63.7%? What is the mean and standard deviation of 61.4%? Using the 68-95-99.7 rule, describe the sampling distribution of 63.7% Using the 68-95-99.7 rule, describe the sampling distribution of 61.4%? Please help I am so lost...

*October 17, 2013 by Lisa*

**statistic**

Let's assume there are 3 people in Room A and another 3 people in Room B. The ages of the people in Room A are 25, 25, and 25. The ages of the people in Room B are: 10, 25, and 40. The mean of the ages in both rooms is 25. Does that mean that both room have populations that ...

*May 12, 2010 by carol*

**statistics**

The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 50 students who took the exam is selected for study: A) What is the shape, mean, and ...

*November 6, 2008 by Marshall*

**Math - Standard Deviation**

A General Electric soft white 3-way bulb has an average life of 1200 hours with a standard deviation of 50 hours. Find the probability that the life of one of these bulbs will be between 1150 and 1300 hours. You need to change the times to Z-scores â€” scores given in terms of...

*July 22, 2005 by GetYourLeash*

**Psychology/Statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size - 3. Use the formula sqrt(N^ 2/S)

*July 15, 2011 by Dawn*

**Algebra**

A supervisor finds the mean number of miles that the employees in a 9the x has a line on top)department live from work. He finds X=2.9 and s=3. Which statement must be true? z376 is within 1 standard deviation of the mean. z37 is between 1 and 2 standard deviations of the mean...

*July 18, 2014 by Junior*

**Statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size 3.

*November 15, 2010 by Barbara*

**Statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*November 19, 2010 by Felicia*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size 3

*January 10, 2011 by melissa*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*January 24, 2011 by kim*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*January 30, 2011 by Anonymous*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size - (b) 3 ?.

*February 13, 2011 by net*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3

*April 4, 2011 by amanda *

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*April 10, 2011 by mama*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*May 12, 2011 by Mae*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3.

*June 13, 2011 by hope*

**statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size 3.

*June 14, 2011 by Reba*

**Statistics**

For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size: 3

*July 4, 2011 by Christy*

**statistics**

For a population that has a standard deviation of q0, figure the standard deviation of the distribution of means for samples of size-(a)2,(b)3,(c)4,(d)9.

*July 6, 2011 by Dorothy*

**Satistics**

Monthly incomes of employees at a particular company have a mean of $5954. The distribution of sample means for samples of size 70 is normal with a mean of $5954 and a standard deviation of $259. Suppose you take a sample of size 70 employees from the company and find that ...

*September 15, 2015 by Suzan*

**Statistics**

A driving machine was employed to hit a sample of 41 each of two different brands of golf balls using the same force each time. The research team measured the distance between the point of impact and where the ball eventually came to rest on the ground. Results are show below...

*June 21, 2010 by Randi*

**statistics**

For a population with a mean of 30 and standard deviation of 6, describe the sampling distribution of the means for samples of N=9.

*November 3, 2009 by Ashley*

**statistics**

Given a data set with the mean = 44 and the standard deviation = 15, what is the value of the Third Quartile?

*September 10, 2010 by angie*

**statistics**

Sample size is 24, Mean rate of 6.50%, Standard Deviation is 1.20. Calculate 90% of confidence interval

*October 14, 2010 by sue*

**statistics**

what percentage of students studied between 30 and 40 hours? Range 10-50, Mean- 35, standard deviation-5.

*October 14, 2010 by kim*

**statistics**

with a mean of 62 and standard deviation of 12, how would you find a proportion greater than 80 and draw it on a curve?

*December 2, 2010 by kaitlyn*

**Statistics**

How large a smaple from a N(80,20) population is needed so that the sampling distribution of the mean has a standard deviation of 1?

*January 4, 2011 by Alana*

**Statistics**

How large a sample from N(80,20) population is needed so that the sampling distribution of the mean has a standard deviation of 1?

*January 4, 2011 by Casey*

**statistics**

in a distribution of scores with a mean of 1500 and a standard deviation of 250, what is the 95th percentile?

*February 26, 2011 by Ruben*

**statistics**

Make up 20 hypothetical scores. Determine their mean, median, mode, and standard deviation.

*June 24, 2011 by Janet*

**statistics**

Assuming that the data are normally distributed with a mean of 45 and a standard deviation of 3.25, what is the z-score for a value of 40?

*October 20, 2011 by Dean*

**statistics**

we have a normal distribution with mean 76 and standard deviation 6.4, find the percent between 69.6 & 76?

*November 8, 2011 by laura*

**statistics**

A random sample of size 36 is taken from a population with mean 50 and standard deviation 5. Find P( < 51.5).

*July 6, 2012 by dave*

**Criminology Statistics**

A given distribution has a mean of 60. A score of 75 had a corresponding z of +2.00. The standard deviation is

*March 1, 2013 by Mariah*

**statistics**

A random sample of 100 of a population Mean is 31 and standard deviation 22 Approximate probability of 28

*April 27, 2013 by Dorri*

**statistics**

population with a mean of 110 and a standard deviation of 6, what is the likelihood of a score of 100 or lower

*July 4, 2013 by carole*

**statistics**

You have an observation of 55, a population mean of 48, and a standard deviation of 1.85. Therefore, the z-score would be:

*February 10, 2014 by Anonymous*

**Statistics**

A sample of n=20 has a mean of M = 40. If the standard deviation is s=5, would a score of X= 55 be considered an extreme value? Why or why not?

*November 9, 2014 by Terri*

**Math**

Can someone explain what to do for the following question. What percentage of a normal distribution is greater than the mean? Give your answer correct to the nearest percent. What formula is used? Because I have to find also 1 standard deviation of the mean and what percentage...

*May 22, 2013 by Sue*

**statistics**

I.use the chebyshev's theorem to find out what percentage of the values will fall between 201 and 257 for a data set with a mean of 229 and standard deviation of 14. II. use the emperical rule to find out two values 68% of the data will fall between for a data set with a mean ...

*October 11, 2010 by mary*

**statistics**

A specific study found that the average number of doctor visits per year for people over 55 is 8 with a standard deviation of 2. Assume that the variable is normally distributed. 1. Identify the population mean. 2. Identify the population standard deviation. 3. Suppose a ...

*April 15, 2013 by Cam*

**Math- Statistics**

A random sample of size 36 is to be selected from a population that has a mean μ = 50 and a standard deviation σ of 10. * a. This sample of 36 has a mean value of , which belongs to a sampling distribution. Find the shape of this sampling distribution. * b. Find the ...

*February 8, 2011 by Tammy*

**statistics**

population mean=42.6 standard deviation=12 n=16 M=34.4. Is this mean a reasonable outcome for a sample of n=16, or is this sample mean very different from what would usually be expected? I obtained a z -score of -2.73. Thus, that would make the sample mean a reasonless outcome...

*May 29, 2008 by Lindy*

**statistics**

An IQ is designed so that the mean is 100 and the standard deviation is 23 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 90% confidence that the sample mean is within 5 IQ ...

*May 19, 2014 by joe*

**Statistics**

Thirty random students took a calc test. If the sample mean was 90 & the standard deviation was 13.9, construct a 99% confidence interval for the mean score of all students. Is the answer 83.03 to 96.97??

*September 14, 2008 by Shannon*

**Statistics**

Suppose that a sample of size 58 is drawn from a population with mean 23 and standard deviation 80. Find the value of , the mean of the distribution of sample means. Wrtie only a number as your answer.

*June 20, 2013 by Anonymous*

**statistics**

. For patients with a certain disease the amount of certain protein in the blood is normally distributed with a mean of 130 and a standard deviation of 5. For patients without the disease the amount of that protein is normally distributed with a mean of 150 and a standard ...

*October 29, 2014 by Anonymous*

**statistics**

For patients with a certain disease the amount of certain protein in the blood is normally distributed with a mean of 130 and a standard deviation of 5. For patients without the disease the amount of that protein is normally distributed with a mean of 150 and a standard ...

*October 30, 2014 by Anonymous*

**Statistics**

A sample of 148 values is randomly selected from a population with mean, μ, equal to 46 and standard deviation, σ, equal to 17. (Give your answers correct to one decimal place.) (a) Determine the interval (smallest value to largest value) within which you would ...

*November 23, 2014 by Dakota*

**statistics**

A student scores 600 on a SAT test. If the population mean of the test scores is 510 and the population standard deviation is 106 point, what is the student’s deviation from the mean?

*December 8, 2011 by violet*

**statistics**

for a distribution standard deviation=10.If every item is increased by 2 then what will new standard deviation?

*September 27, 2011 by Anonymous*

**statistics**

for a distribution standard deviation=10.If every item is increased by 2 then what will new standard deviation?

*September 27, 2011 by ria*

**statistics**

a research participant has her brain scanned while listening to music and solving math problems, and the brain area of interest has a percent signal change of 58. From many previous studies with this same math-problems procedure (but not listening to music), it is known that ...

*January 13, 2012 by Anonymous*

**math**

find the standard deviation for the following: 8,5, 12, 8, 9, 15, 21, 16, 3. There is a formula but our teacher wants us to do it a specific way. For example, 47, 41, 32, 53, 57. First you find the mean, which is 46 and then subtract it with each number in the set so you get 1...

*December 8, 2013 by sarah*

**Statistics**

The law of large numbers tells us what happens in the long run. Like many games of chance, the numbers racket has outcomes so variable - one three-digit number wins $600 and all others win nothing - that gamblers never reach "the long run." Even after many bets, their average ...

*February 25, 2014 by Ray*

**Statistics**

The law of large numbers tells us what happens in the long run. Like many games of chance, the numbers racket has outcomes so variable - one three-digit number wins $600 and all others win nothing - that gamblers never reach "the long run." Even after many bets, their average ...

*February 25, 2014 by Ray*

**Statistics**

The law of large numbers tells us what happens in the long run. Like many games of chance, the numbers racket has outcomes so variable - one three-digit number wins $600 and all others win nothing - that gamblers never reach "the long run." Even after many bets, their average ...

*February 25, 2014 by PLEASE HELP!!!!!!!!!*

**Math**

On a standardized test, Phyllis scored 84, exactly one standard deviation about the mean. If the standard deviation for the test is 6, what is the mean score for the test?

*October 22, 2012 by Tanyetta*

**math**

A district mathematics test for all third graders had a normal distribution with a mean of 74 and a standard deviation of 11. What percentage of the third graders tested scored with +1 and -1 standard deviation of the mean?

*July 5, 2013 by Anonymous*

**Math (statistics)**

The probability of obtaining heads on a biased coin is 0.4. The coin is tossed 600 times. a. i. Write down the mean number of heads (240) ii. Find the standard deviation of the number of heads (12) b. Find the probability that the number of heads obtained is less than one ...

*March 16, 2016 by Myra*

**Statistics**

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.

*July 17, 2012 by Christie*

**statistics**

it is stated that the standard deviation sample of the is 7.6 (n = 26). Test the claim to a significance level of 0.10 that the population standard deviation was greater than 7.0. Round all answers to 3 decimal places.

*July 28, 2012 by geety*

**statistics**

it is stated that the standard deviation sample of the is 7.6 (n = 26). Test the claim to a significance level of 0.10 that the population standard deviation was greater than 7.0. Round all answers to 3 decimal places.

*July 28, 2012 by geety*

**QNT/351**

Describe a business situation, other than what has already been selected by fellow students or selected from the team assignment, where mean and standard deviation can be used in decision making. Describe how calculation of mean and standard deviation can help in making a ...

*November 26, 2013 by Karen*

**adult education**

The lifetimes of lightbulbs of a particular type are normally distributed with a mean of 290 hours and a standard deviation of 6 hours. What percentage of the bulbs have lifetimes that lie within 1 standard deviation to either side of the mean?

*May 23, 2009 by sally*

**Math**

Would you rather take an exam that typically has an mean of 80 with a standard deviation of 3 or an exam with a mean of 80 with a standard deviation of 15? why?

*December 2, 2010 by Rena *

**Math**

Would you rather take an exam that typically has an mean of 80 with a standard deviation of 3 or an exam with a mean of 80 with a standard deviation of 15? why?

*December 3, 2010 by Rena *

**Math**

if a test given to 100 people have a mean of 3.5 and a standard deviation is .5, what is the standard deviation of someone who scores 1.5>

*April 8, 2009 by Debra*

**math**

if a test given to 100 people have a mean of 3.5 and a standard deviation is .5, what is the standard deviation of someone who scores 1.5?

*April 8, 2009 by Debra*

**Data and statistics**

If a student had a z score of 2.5 for IQ, whar is his actual IQ? The IQ mean is 100, and standard deviation is 15.

*July 22, 2010 by Beverly*

**business statistics**

solv the following a)mean b)mode c)median d)standard deviation observation Frequency 5 14 10 22 15 47 20 17

*November 29, 2010 by Anonymous*