# math: standard deviation

145,664 results

### Math

Roughly speaking, the standard deviation indicates how far, on average, the observations are from the mean. Do you think that for the data set below the standard deviation will give a good indication of the typical deviation from the mean? 2, 3, 4, 4, 5, 5, 6, 6, 100 What ...

### Algebra

Use a calculator to find the mean and standard deviation of the data. Round to the nearest tenth. 6,7,19,7,18,7 A. mean = 9; standard deviation = 26.4 B. mean = 11.9; standard deviation = 26.4 C. mean = 10.6; standard deviation = 6.1 D. mean = 9; standard deviation = 5.1 For ...

### math standard deviation

Calculate the standard deviation for the following yields of corn: 142, 161, 132, 143, 147, 145, 146, and 152 bu/ac. Are all yields obtained within one standard deviation of the mean?

### math: standard deviation

Calculate the standard deviation for the following yields of corn: 142, 161, 132, 143, 147, 145, 146, and 152 bu/ac. Are all yields obtained within one standard deviation of the mean?

### Statistics (Math 210)

Hi there, I am doing my statistics homework and am having trouble with a few problems. I sincerely appreciate any help I receive! :) A manufacturer claims the standard deviation of salt in their meat is .5. An SRS of 18 samples shows the standard deviation (s)= .62 (alpha = ....

### 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.

### college math

20. Calculate the range, variance, and standard deviation of the following data set: 5, 5, 6, 6, 6, 8, 8, 8, 8, 10, 10, 11, 12, 12, 20 (Points: 5) Range = 15; Variance = 225; Standard Deviation = 7.5 Range = 3.85; Variance = 14; Standard Deviation = 3.74 Range = 20; Variance...

### math

Suppose x is a random variable with mean and standard deviation. If a large number of trials is observed, at least what percentage of these values is expected to lie beween mean-2(standard deviation) and mean + 2(standard deviation) could someone help me i'm so lost? thank you...

### Statistics

1) A Motor Company has purchased steel parts from a supplier for several years and has found that 10% of the parts must be returned because they are defective. An order of 25 parts is received. What are the mean and standard deviation of the defective parts? A) Mean = 3.5; ...

### Stastics

When we convert x-value to z- score and use Standard Normal distribution, which of the following statements is true? a) The mean of z-score is zero and standard deviation of the z-scores is the same as the standard deviation of original data b) The mean and standard deviation ...

### math...Please help!!!!

This is a standard deviation question. I don't know much about standard deviation. Here it goes... Teachers making 30,000 to $60,000 the union is considering a $1,000 pay raise. A. Will the standard deviation change and the mean and the median stay the same? B. Will the mean ...

### Statistics

A college statistics class conducted a survey of how students spend their money. They asked 25 students to estimate how much money they typically spend each week on fast food. They determined that the mean amount spent on fast food is $31.52 with a standard deviation of $21.60...

### math

hi i need help calculating the standard error using the central limit theorem. *a population of scores contains exactly 5 scores : 2, 3, 6, 8, 11, there are 5x5=25 samples of the two scores (n=2)* i already calculated the standard deviation and mean. for the question my ...

### Statistics

data from sample of 400 cases, variable has 95% confidence interval of 54.3 to 54.7 I found the mean- how do i find standard error- step by step please. Standard error = sd/√n Note: sd = standard deviation; n = sample size. You'll need to determine the standard deviation...

### Math: Statistics

My homework has a list of numbers and I'm working with standard deviation. I know the standard deviation as well as the mean and everything, but it says to find "the weight that is 3 standard deviations below the mean." What is the formula for that, and can I do it on a TI-84...

### statistics

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...

### 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...

### statistics

A researcher administered a treatment to a sample of participants selected from a population of 80. If the researcher obtains a sample mean of M=88. Which combination of factors is most likely to result in rejecting the null hypothesis? a, alpha level=0.01 and standard ...

### MATH

A mean score on a standardized test is 50 with a standard deviation of 10. Answer the following a. What scores fall between –1 and +1 standard deviation? b. What percent of all scores fall between –1 and +1 standard deviation? c. What score falls at +2 standard deviations...

### 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>

### 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?

### Math, Please Help

Describe a scenario where you expect a set of data to have A.) a large standard deviation B.) a small standard deviation

### Satistics

5. Give the standard deviation for the mean and median column. Compare these and be sure to identify which has the least variability? Standard deviation of Mean = 0.476169 Standard deviation of Median = 0.753937

### Statistics

If the standard deviation of a population is 56 and we want the standard error (the standard deviation of the sample mean) to be 14, then we need to take how many samples?

### Math

X is a normal variable with mean 9. If P(X > 12) = 0.0062, calculate the standard deviation, the standard deviation if X.

### Math

Describe a scenario where you expect a set of data to have A.) a large standard deviation B.) a small standard deviation The prize for winning a contest can be chosen from category a or category b. Prizes from category a have a mean of $1000 and a standard deviation of $50. ...

### Math

The mean of a sample of 25 was calculated as xbar = 500. The sample was randomly drawn from a population whose standard deviation is 15. Estimate the population mean with 99% confidence. B.) Repeat part (a) changing the population standard deviation to 30. C.) Repeat part (a) ...

### Statistics

hi i need help calculating the standard error using the central limit theorem. *a population of scores contains exactly 5 scores : 2, 3, 6, 8, 11, there are 5x5=25 samples of the two scores (n=2)* i already calculated the standard deviation and mean. for the question my ...

### math

what is the standard deviation of the numbers {78, 79, 81, 82, 85}. And can you tell me how i am supposed to find the standard deviation

### 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 ...

### math

The standard deviation of a sample taken from population A is 17.6 for a sample of 25. The standard deviation of a sample taken from population B is 21.2 for a sample of 30. The standard deviation of the sample mean differences is_____. (Round your answer to the nearest ...

### statistics

150 students is 60 kg the mean of body is 70 kg withstandard deviation of 10 kg and mean weight of girls is 55 kg with standard deviation of 15kg.calculate the number of boys and the combined standard deviation. Also find whether the coefficient of deviation is hired for girls...

### MATH

Which of the following normal distributions has the smallest spread? A. A normal distribution with mean 1 and standard deviation 3 B. A normal distribution with mean 0 and standard deviation 2 C. A normal distribution with mean 3 and standard deviation 2 D. A normal ...

### statistics/mean and standard deviation

find the mean and standard deviation in the following probability distribution x 1 2 3 p(x) 0.2 0.6 0.2 *i think that the mean is 2 but am lost after that when it comes to the standard deviation. please show work and calculations. the more i work with numbers the more confused...

### College Chem

Please tell me if this is correct...Finding the mean, the average deviation from the mean, the standard deviation from the mean, and the relative deviation from the mean...of 10.1, 10.4 and 10.6 Mean-10.4 Average deviation-0.167 Standard deviation-0.25 Relative deviation-2%

### Statistics

1) Find the missing parameter 1.mean 15, 30.15 %, above 50; what is the standard deviation 2.mean 75, 5.05% below 30; what is the standard deviation 3.standard deviation 9, 85.08% below 105: what is the mean 4.standard deviation 16.8, 15.62% above 18.3: what is the mean

### Statistics: Range, Average Deviation, Standard Dev

Can someone please help me with the following math problems? I am totally lost and confused. Calculate the range, average deviation, and standard deviation for the following five distributions: A. 1, 2, 3, 4, 5, 6, 7, 8, 9 B. -4, -3, -2, -1, 0, 1, 2, 3, 4 C. 10, 20, 30, 40, 50...

### Math

The mean score on the exit examination for an urban high school is 63 with a standard deviation of 9. What is the standard deviation of the distribution of sample means with a sample size of 9? A. 2 B. 3 C. 4 D. 4.1 answer B

### Math ---HELP!!!!!

The mean score on the exit examination for an urban high school is 63 with a standard deviation of 9. What is the standard deviation of the distribution of sample means with a sample size of 9? A. 2 B. 3 C. 4 D. 4.1 answer B

### math

the prison popuation of 9 different countries are: 50, 30, 10, 50, 60, 50, 20, 40, 50. What is the range and standard deviation? Explain. I know the range is 50, but i cant figure out the standard deviation.

### math

the prison popuation of 9 different countries are: 50, 30, 10, 50, 60, 50, 20, 40, 50. What is the range and standard deviation? Explain. I know the range is 50, but i cant figure out the standard deviation.

### Statistics

Given that x is a normally distributed random variable with a mean of 28 and a standard deviation of 7, find the following probability: P(x<28) I understand that the means is 28 and the standard deviation is 7. However what I don't understand is how to get the value of x. ...

### Math

1. An assembly line produces widgets with a mean weight of 10 and a standard deviation of 0.200. A new process supposedly will produce widgets with the same mean and a smaller standard deviation. A sample of 20 widgets produced by the new method has a sample standard deviation...

### Statistics/ is this how I do it.

Find the range and the standard deviation (correct to two decimal places). 83,96,100,100,103 find the range and standard deviation Do I that 5 numbers add that divide by 5 for the range I am not sure how to do standard deviation. Thank you

### statistics

If a company is thinking of giving one department a 1000 bonus. Based on their means and standard deviation scores which set of employess will do better based on this information? Who should get the bonus? Employee A mean 16.875 standard deviation 4.45413 Employee B mean 12....

### Math

Repeated sample of 36 are drawn from a population with mean 52 and standard deviation 18. What is the standard deviation of the distribution of the sample means?

### MATH

what is the unknown standard deviation of this problem Ho: m=4.7 Ha: m<4.7 alpha 1% standard deviation: unknown after a random sample of 36 the mean is 4.5 with s=0.42

### Math

Find the 95% confidence interval for the standard deviation of the lengths of pipes if a sample of 26 pipes has a standard deviation of 10 inches

### math

Using the data in the table, calculate the mean, range, variance, and standard deviation, and then answer questions e and f. Round the variance and standard deviation to one decimal place. a. Mean b. Range c. Variance d. Standard deviation e. What value is affecting the mean ...

### 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 ...

### Chemistry/Normal Distributions/Math

I'm confused on how to calculate the standard deviation for this... The 95% confidence limit for calcium in control sera is reported as 9.2-10.2 mg/dl. Calculate the value for one standard deviation and the coefficient of variation for this data.

### 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 ...

### Advanced Functions

1. Find the following quantities by hand (except for the standard deviation) Check your results with your calculator: a. Minimum b. Lower Quartile c. Median d. Upper Quartile e. Maximum f. Range g. Mean h. Mode i. Standard deviation 2. Is the mean or median a better measure of...

### probability and statistics

Suppose every student in your class got a score of 85% on an exam. What are the mean and standard deviation of those exam scores without doing any calculations? I want to say the mean is 100 and the standard deviation is 1 but I don't know why. If all students scored 85% that ...

### stats

Why must you square the deviation scores when computing a standard deviation using the definitional formula? Why is the computational formula easier to use when computing variance and standard deviation?

### 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.

### 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

### stATS

the standard deviation of the sampling distribution of the means is ____the standard deviation of the population under study.

### statistics

population has mean 53 and standard deviation 12. Calculate the standard deviation of x bar for a random sample of size 12.

### statistics

a mean score on a standardized test is 50 with a standard deviation of 10. What are the following: 1. what scores fall between -1 and +1 standard deviation? 2. what percent of all scores fall between -1 and +1 standard deviation? 3. what score falls at +2 standard deviations? ...

### 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...

### 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)

### 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.

### 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.

### psy325

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

### 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

### 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.

### 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.

### psychology

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 ?.

### 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 ?.

### 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

### 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.

### 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.

### 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.

### 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.

### 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

### 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.

### econ

12) Suppose you know that the standard deviation of a variable is 10, and you have 100 observations, the standard deviation of the mean is

### Stats

You are allowed to choose four whole numbers from 1 to 10 (including 1 and 10). You can only choose each number once though. Which of the following statements is FALSE? A. The numbers 4, 5, 6, and 7 have the smallest possible standard deviation. B. The numbers 1, 2, 3, and 4 ...

### Chemistry

Calculate the value of Z and its absolute standard deviation. All standard deviations shown are absolute. Show your work and report the standard deviation in the result with two significant digits (to confirm the correct result). Z = (1.18+/-0.07)x((2.21+/-0.05)^3)

### standard deviation

the mean is 3.5. dtandard deviation is .5. sally's score is 1.5 on test. how many standard deviations is she from the mean? billy scores 5. what is his standard score? what scale of measurement is being used? is it appropriate? why/why not?

### 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 ...

### statistics

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

### statistics

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

### 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.

### 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.

### Statistics

9 points) In a normally distributed data set, find the value of the standard deviation if the following information is given. a. The mean is 226.2. x = 230. z = 0.2. Standard deviation

### math

Using the data in the table, calculate the mean, range, variance, and standard deviation, and then answer questions e and f. Round the variance and standard deviation to one decimal place. a. Mean b. Range c. Variance d. Standard deviation e. What value is affecting the mean ...

### math

Using the data in the table, calculate the mean, range, variance, and standard deviation, and then answer questions e and f. Round the variance and standard deviation to one decimal place. a. Mean b. Range c. Variance d. Standard deviation e. What value is affecting the mean ...

### statistics

help! where do i begin with this problem...in one area, monthly incomes of technology related workers have a standard deviation of $650. It is believed that the standard deviation of monthly incomes of non-technology workers is higher. A sample of 71 non technology workers are...

### HELPP math

13,14,29,26,41,53,60,7,89,14 Based on the numbers above what is the variance and the standard deviation of the data set. I think 616.2 is the variance I think 24.83 is the standard deviation Am I correct????

### statistics

A student was asked to compute the mean and standard deviation for the following sample of n _ 5 scores: 81, 87, 89, 86, and 87. To simplify the arithmetic, the student first subtracted 80 points from each score to obtain a new sample consisting of 1, 7, 9, 6, and 7. The mean ...

### Maths

Statistics The marks scored by a sample of 56 students are summarised by: N=56 Sum of x =3026 sum of(x-the mean)^2 =15378 A) calculate the mean and the standard deviation Mean I got - 54.04 (2.dp) Standard deviation I got - 16.72 (2.dp) Is this correct? B) the formula y=1.2x-...

### Maths

Statistics The marks scored by a sample of 56 students are summarised by: N=56 Sum of x =3026 sum of(x-the mean)^2 =15378 A) calculate the mean and the standard deviation Mean I got - 54.04 (2.dp) Standard deviation I got - 16.72 (2.dp) Is this correct? B) the formula y=1.2x-...

### statistics

A production process is considered to be out of control if the produced parts have lengths with a standard deviation greater than .5 mm. A sample of 41 parts yields a sample standard deviation of .58 mm. At the .05 significance level, does this sample indicate that the process...

### Chemistry

What is the difference between Residual Standard Deviation and Relelative Standard Deviation?

### Chemistry

What is the difference between Residual Standard Deviation and Relative Standard Deviation?

### 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...

### math

Miss C gives a test to the 10 students in her first-period algebra class. The grades are 93,82,95,86,90,84,89,79,87,93 A. Find the mean and Standard Deviation of the 10 scores. B. List all the reasons for why the late class could have a different mean or standard deviation