Saturday

April 19, 2014

April 19, 2014

Number of results: 18,666

**Statistics**

Which test determines if there is a difference between the mean of a group and proposed standard value? Paired t-test F-test One Sample t-test One way ANOVA Two sample t-test
*Wednesday, September 15, 2010 at 9:13am by Beata Chmielewska*

**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*

**AP BIO**

a student wished to test a sample of organic material to determine whether it was sugar, a dat, or starch. If she could perform only one of the following, which would be the most revealing? 1- test for the presence of carbon and hydrogen in the sample 2- test the sample to ...
*Wednesday, October 7, 2009 at 5:43pm by bubba*

**statistics**

7. A sample of 40 observations is selected from one population. The sample mean is 102 and the sample standard deviation is 5. A sample of 50 observations is selected from a second population. The sample mean is 99 and the sample standard deviation is 6. Conduct the following ...
*Sunday, February 28, 2010 at 11:51pm by Barbara*

**Statistics**

8. A sample of 65 observations is selected from one population. The sample mean is 2.67 and the sample standard deviation is .75. A sample of 50 observations is selected from a second population. The sample mean is 2.59 and the sample standard deviation is .66. Conduct the ...
*Sunday, February 28, 2010 at 11:52pm by Barbara*

**Statistics**

The effectiveness of a headache medicine is tested by measuring the intensity of a headache in patients before and after drug treatment. The data consist of before and after intensities for each patient. Identify the design of the study. A) Paired t-test B) Two-sample t-test C...
*Thursday, November 21, 2013 at 6:40pm by Samantha*

**Statistics**

You can use a one-sample proportional z-test for your data. (Test sample proportion = .58 and sample size = 150) Find the critical value in the appropriate table at .01 level of significance for a two-tailed test. Compare the test statistic you calculate to the critical value ...
*Friday, May 11, 2012 at 3:28pm by MathGuru*

**Statistics**

. A random sample is selected from a normal population with a mean of __40 and a standard deviation of __10. After a treatment is administered to the individuals in the sample, the sample mean is found to be M _ 42. a. How large a sample is necessary for this sample mean to be...
*Thursday, January 26, 2012 at 10:04pm by Sharon*

**statistics z or t test **

the average weekly earnings of a production worker were $424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is $432.69, with a sample standard deviation of $33.90. Use a 0.05 ...
*Monday, July 19, 2010 at 1:01pm by Anonymous*

**Probabilty & Statistic**

A random sample is selected from a normal population with a mean of __40 and a standard deviation of __10. After a treatment is administered to the individuals in the sample, the sample mean is found to be M _ 42. a. How large a sample is necessary for this sample mean to be ...
*Monday, January 23, 2012 at 4:39pm by Sharon*

**Statistic**

You can use a one-sample proportional z-test for your data. (Test sample proportion = 39/90 and sample size = 90) Convert fractions to decimals to use in the z-test. Find the critical value in the appropriate table at .05 level of significance for a two-tailed test. Compare ...
*Monday, July 9, 2012 at 10:41pm by MathGuru*

**stats**

1. FOR A ONE-TAILED TEST with alpha .01 = 2.33 (round accordingly) 2. Use a z-test to determine your test statistic. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Your data: sample mean = 55 population mean = 35 standard...
*Tuesday, October 23, 2012 at 4:46pm by MathGuru*

**t test **

how to know exact t value using sample standard deviation and sample mean and sample size i think df is sample size -1 . we usually use approx value but to use exact value how to use t score table. and how we conclude whether it is two tailed test or one tailed test . (i f the...
*Sunday, July 18, 2010 at 6:50pm by Anonymous*

**statistics t test **

how to know exact t value using sample standard deviation and sample mean and sample size i think df is sample size -1 . we usually use approx value but to use exact value how to use t score table. and how we conclude whether it is two tailed test or one tailed test . (i f the...
*Sunday, July 18, 2010 at 10:03pm by Anonymous*

**Stats**

Try a one-sample z-test or t-test, depending on the size of your sample. Check the appropriate table at 0.01 level of significance for a two-tailed test. Once you calculate the test statistic, compare to the critical or cutoff value(s) from the table to reject or fail to ...
*Monday, May 20, 2013 at 12:34pm by MathGuru*

**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*

**MATH STATS**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Monday, July 4, 2011 at 2:06am by Vanessa*

**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**

1.test wheter these samples represent populations that are different from the general population- sample of 10 with a mean of 44 and sample of 1 with a mean of 48. 2. The general population of individuals has a mean of 40 , a deviation of 6, and follows a normal curve. for ...
*Friday, October 22, 2010 at 9:23am by Stephanie*

**Statistics**

Which one of the following test is used to compare five means, simultaneously? Run test Normally test One way ANOVA 2 Sample T Test F-Test
*Wednesday, September 15, 2010 at 9:11am by Beata Chmielewska*

**statistics**

Null hypothesis: p = .40 Alternate hypothesis: p does not equal .40 You can use a one-sample proportional z-test for your data. (Test sample proportion = .37 and sample size = 100) Find the critical value in the appropriate table at .01 level of significance for a two-tailed ...
*Thursday, July 19, 2012 at 9:31pm by MathGuru*

**statistics t test immediate help needed**

the average weekly earnings of a production worker were $424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is $432.69, with a sample standard deviation of $33.90. Use a 0.05 ...
*Sunday, July 18, 2010 at 10:03pm by Anonymous*

**statistics**

the average weekly earnings of a production worker were $424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is $432.69, with a sample standard deviation of $33.90. Use a 0.05 ...
*Sunday, July 18, 2010 at 10:10pm by Anonymous*

**statistics 4.**

Here are a few ideas to get you started. First problem: Try a one-sample z-test. Formula: z = (sample mean - population mean)/(standard deviation divided by the square root of sample size) Your data: sample mean = 2.6 population mean = 2.5 standard deviation = 0.5 sample size...
*Tuesday, December 17, 2013 at 5:23pm by MathGuru*

**Statistic**

A restaurant that bills its house account monthly is concerned that the average monthly bill exceeds $200 per account. A random sample of twelve accounts is selected, resulting in the sample mean of $220 and a sample standard deviation of $12. The researchers have determined ...
*Monday, October 20, 2008 at 12:22am by Marilyn*

**Statistics**

You can use a one-sample proportional z-test for your data. (Test sample proportion = 24/200 and sample size = 200) Convert all fractions to decimals. Find the critical value in the appropriate table at .01 level of significance for a two-tailed test. Compare the test ...
*Thursday, July 19, 2012 at 10:57am by MathGuru*

**statistics**

You are conducting an experiment to see if a given therapy works to reduce test anxiety in a sample of college students. A standard measure of test anxiety is known to produce a = 19. In the sample you draw of 86 the mean is equal 17.5 with standard deviation s = 10. a- Use ...
*Friday, January 6, 2012 at 1:03pm by sai*

**STATS**

Given a sample size of 18, 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 1. What is the critical value for this test? ...
*Tuesday, March 30, 2010 at 12:27am by Mary*

**Statistics**

If you use a one-sample z-test, here is the formula: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (132.3 - 128)/(15/√50) = ? Finish the calculation. Check a z-table at 0.05 level of ...
*Tuesday, April 16, 2013 at 6:18pm by MathGuru*

**Statistics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (43.5 - 40)/(8/√100) = ? Finish the calculation. Check a z-table at .05 level of significance for a one-tailed test. If the...
*Friday, April 27, 2012 at 7:55am by MathGuru*

**Stats**

Consider the following Hypotheses test: Ho:m>=80 Ha:m<80 A sample of 121 provided a sample mean of 77.3. The population Standard Deviation is known to be 16.5. A. compute the value of test statistic B. Determin the p value: and at 93.7% confidence, Test the above ...
*Sunday, April 29, 2012 at 11:24pm by bobbie*

**statistics**

You can use a one-sample proportional z-test for your data. (Test sample proportion = 76/120 or .63) Find the critical value in the appropriate table at .05 level of significance for a one-tailed test. Compare the test statistic you calculate to the critical value from the ...
*Tuesday, August 2, 2011 at 12:32am by MathGuru*

**statistics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (38250 - 39000)/(1200/√18) = ? Finish the calculation. Check a z-table at .05 level of significance for a one-tailed test. ...
*Tuesday, June 8, 2010 at 1:45pm by MathGuru*

**statistics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (38.7 - 40)/(12.5/√50) = ? Finish the calculation. Check a z-table at .05 level of significance for a one-tailed test. If ...
*Sunday, February 24, 2013 at 1:15pm by MathGuru*

**statistics**

You can probably use a one-sample proportional test for your data. (Test sample proportion = 65/80 or .8125) Find the appropriate table for your critical value at .10 level of significance for a one-tailed test. Compare the test statistic you calculate to the critical value ...
*Friday, February 17, 2012 at 12:47am by MathGuru*

**Statistics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (5.25 - 4.75)/(1.15/√52) = ? Finish the calculation. Check a z-table at .01 level of significance for a one-tailed test. If...
*Sunday, May 5, 2013 at 4:51pm by MathGuru*

**statistics**

A researcher wants to carry out a hypothesis test involving the mean for a sample of n = 20. While the true value of the population standard deviation is unknown, the researcher is reasonably sure that the population is normally distributed. Given this information, which of ...
*Tuesday, July 31, 2012 at 2:35am by Anonymous*

**statistic**

You can probably use a one-sample proportional test for your data. (Test sample proportion = 20/55 or .36) Find the appropriate table for your critical value at .10 level of significance for a one-tailed test. Compare the test statistic you calculate to the critical value from...
*Tuesday, August 2, 2011 at 12:40am by MathGuru*

**statistics**

Try a one-sample t-test since the sample size is fairly small. This will be a one-tailed test (the alternate hypothesis will show a specific direction). Formula for a one-sample t-test is the following: z = (sample mean - population mean)/(standard deviation divided by the ...
*Tuesday, March 5, 2013 at 9:47pm by MathGuru*

**Statistics**

This appears to be a hypothesis test involving inferences concerning two variances. Sample 1 (Girls): n = 21; variance = 100; df = n - 1 = 20 Sample 2 (Boys): n = 25; variance = 169; df = n - 1 = 24 Test statistic = sample 1 variance / sample 2 variance You can use the F-...
*Monday, January 27, 2014 at 10:22am by MathGuru*

**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*

**Walker**

Given: You are using a significance level of = 0.05 to test a claim that p > 0.5. Your sample is a simple random sample of size n = 49. Calculate for the test, assuming that the true population proportion is 0.7 and showing all work.
*Monday, March 12, 2012 at 1:37pm by Buster*

**Prob and Stat**

Use a one-sample z-test. Formula: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With the data in your problem: z = (58000 - 60000)/(7000/√49) Finish the calculation. If the test statistic exceeds the critical value...
*Tuesday, May 17, 2011 at 2:15pm by MathGuru*

**MATH-STAT**

You can use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (81.5 - 84)/(10/√75) = ? I'll let you finish the calculation. If you use a 1% significant level for a two-tailed ...
*Thursday, November 21, 2013 at 2:53pm by MathGuru*

**Statistics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (522.3 - 530)/(29/√85) = ? Finish the calculation. Check a z-table at .01 level of significance for a two-tailed test (H1 ...
*Friday, March 8, 2013 at 9:35pm by MathGuru*

**statistics**

Try a t-test since your sample size is rather small. Ho: = 60 -->null hypothesis Ha: > 60 -->alternative hypothesis Formula: t = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) sample mean = 70 population mean = ...
*Thursday, May 10, 2012 at 3:18pm by MathGuru*

**Statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: A. a sample of 10 with a mean of 44. B.a sample of 1 with a mean of 48. The general population of ...
*Monday, November 15, 2010 at 5:34pm by Barbara*

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Friday, November 19, 2010 at 2:07pm by Anonymous*

**Statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Friday, November 19, 2010 at 2:09pm by Felicia*

**psy325**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Wednesday, December 15, 2010 at 12:05am by smith*

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Monday, January 24, 2011 at 2:17pm by kim*

**Statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Monday, April 4, 2011 at 9:40am by amanda *

**Statistics**

: For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Wednesday, June 15, 2011 at 9:29pm by Stephanie *

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Sunday, June 19, 2011 at 1:26pm by val*

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Monday, June 27, 2011 at 7:59pm by brie*

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Wednesday, July 6, 2011 at 11:02pm by Dorothy*

**statistics**

For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general population: (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Tuesday, July 19, 2011 at 9:03pm by shawn*

**Biochemistry**

1.How to test a sample with cholesterol? - Name of test? - Procedure of test? - Results
*Wednesday, April 20, 2011 at 10:28am by Haldriech*

**Statistics**

The ____________ is a hypothesis-testing procedure in which there are two separate groups at people tested and the population variance is not known. - t test for dependent means - t test for a single sample - t test for independent means - t test for repeated measures
*Sunday, October 11, 2009 at 10:15am by Trey*

**biostatistic**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (38 - 60)/(19/√50) = ? Finish the calculation. Check a z-table at .05 level of significance for a one-tailed test. If the z...
*Tuesday, November 20, 2012 at 1:37pm by MathGuru*

**Math**

You are using a significance level of = 0.05 to test a claim that p > 0.5. Your sample is a simple random sample of size n = 49. Calculate type II error for the test, assuming that the true population proportion is 0.7 and showing all work.
*Monday, March 12, 2012 at 2:31pm by Bee*

**Science **

In a one sample test, a sample is compared with a standard or benchmark. In a two sample test, the samples compared a. with two alternate hypotheses b. with an historical and a future benchmark c. with each other d. with opposing samples
*Monday, December 19, 2011 at 3:52pm by Debra *

**math-stupid stat**

You can use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (11.6 - 13)/(1.3/√7) = ? Finish the calculation. If you use an alpha of .02 for a two-tailed test, then the cutoff ...
*Thursday, November 21, 2013 at 2:56pm by MathGuru*

**statistics**

Suppose that the population standard deviation () for a normally distributed standardized achievement test (ACT) is 6. What would the standard error of the sample mean (xbar) be if we were to draw a random sample of 36 test scores?
*Tuesday, October 4, 2011 at 3:53pm by Anonymous*

**statistics**

There are t-tables that show values for one-tailed and two-tailed tests. Since the test is right-tailed, this is a one-tailed test. If n = 21, degrees of freedom would be n - 1, which is 20. (I'm assuming this was a one-sample t-test. If not, the degrees of freedom would be ...
*Friday, May 21, 2010 at 6:26pm by MathGuru*

**college Math**

Ho: = 40 --->meaning the population mean is equal to 40. H1: < 40 ---> meaning the population mean is less than 40. This will be a one-tailed test because the alternative hypothesis is showing a specific direction. Use a z-test. Find the significance level for a ...
*Monday, December 7, 2009 at 8:30pm by MathGuru*

**Statistics**

Try a one-sample z-test for your problem. Using the z-test formula to find the test statistic: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) z = (3.69 - 3.65)/(.24/√45) Finish the calculation. Use a z-table to ...
*Thursday, September 11, 2008 at 1:29am by MathGuru*

**Statistics**

Using the z-test formula to find the test statistic: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) z = (46500 - 47000)/(5500/√30) z = ? Finish the calculation.
*Tuesday, June 7, 2011 at 11:37am by MathGuru*

**AP Statistics**

You can try a proportional one-sample z-test for this one since this problem is using proportions. Using a formula for a proportional one-sample z-test with your data included, we have: z = .16 - .10 -->test value (13/81 is .16) minus population value (.10) divided by &#...
*Wednesday, October 31, 2012 at 11:21am by MathGuru*

**STAT**

Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : = 700 Research Hypothesis H1 : ≠ 700 What is the test statistics? At a 0.05 significance level, what is ...
*Saturday, October 12, 2013 at 12:27pm by Jacky*

**STAT**

Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : = 700 Research Hypothesis H1 : ≠ 700 What is the test statistics? At a 0.05 significance level, what is ...
*Sunday, October 13, 2013 at 9:15am by Jacky*

**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**

Since the sample size is small, you can use a t-test: t = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: t = (6.91 - 7.48)/(1.21/√24) Finish the calculation. Check a t-table using n - 1 for degrees of ...
*Tuesday, April 19, 2011 at 11:57pm by MathGuru*

**Economics 210**

Information given is sample mean of 12 for a sample of 26. Sample deviation is 3. Using a .02 level of significance. H0 u< or equal to 10 and H1 u> 10 a. Is this a one or two tailed test? b. what is the decision rule? c. what is the value of the test statistic? d.what is...
*Tuesday, May 3, 2011 at 7:32pm by Daniel*

**immediate help needed statistics one tailed hypo**

the average weekly earnings of a production worker were $424. to know if wages, on average, have gone up since that time. To test this, you sample 64 production workers, and determine that their average salary is $432.69, with a sample standard deviation of $33.90. Use a 0.05 ...
*Monday, July 19, 2010 at 5:36pm by Anonymous*

**Stastics**

Use a one-sample z-test. z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Note: Standard deviation is the square root of the variance. Check a z-table at .05 level of significance for a one-tailed test. If the z-test ...
*Wednesday, April 3, 2013 at 1:40pm by MathGuru*

**sssc**

Suppose we test H0 : p = .3 versus Ha : p ≠ .3 and that a random sample of n = 100 gives a sample proportion p = .20. a: Test H0 versus Ha at the .01 level of significance by using critical values. What do you conclude? b: Find the p-value for this test. c: Use the p-...
*Monday, June 11, 2012 at 3:22pm by Anonymous*

**statistics**

an auditor wishes to test the assumption that the mean value of all accounts receivable in a given firm is $260.00 she will reject this claim only if it is clearly contradicted by the sample mean. the sample standard deviation of 36 accounts is $43, the sample mean is $250, ...
*Sunday, April 29, 2012 at 1:51pm by b*

**Statistics**

Use the z-test formula to find the test statistic: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Plug the values given into the formula to calculate your z-test statistic. Since the H1 shows a specific direction, this ...
*Saturday, March 13, 2010 at 8:59pm by MathGuru*

**Statistics**

A sample of 64 observations is selected from a normal population. the sample mean is 215 and the standard deviation is 15. conduct the following test of hypothosis using the .3 significance level. Ho:u > or = 220 H1: u < 220 a) Is this a 1 tailed or 2 tailed test? b) ...
*Friday, October 3, 2008 at 3:08pm by Shawn*

**business statistics**

Using the z-test formula to find the test statistic: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) z = (230.8 - 220)/(17/√12) Finish the calculation. Since this sample is from a normally distributed population, use...
*Wednesday, July 29, 2009 at 4:47pm by MathGuru*

**statistics**

Both parts are using one-sample two-tailed tests. Since the sample in part a) is so small, you can try a one-sample t-test and for part b), a one-sample z-test. For the t-test: t-statistic = (sample mean - population mean)/(standard deviation divided by the square root of the ...
*Thursday, February 28, 2008 at 1:37am by MathGuru*

**statistics**

Using a formula for a binomial proportion one-sample z-test with your data included, we have: z = .25 - .18 -->test value (310/1240 = .25) minus population value (.18) divided by √[(.18)(.82)/1240] -->.18 is test value, .82 is 1 - .18, and 1240 is the sample size ...
*Tuesday, October 5, 2010 at 4:16pm by MathGuru*

**AP Statistics**

You can try a proportional one-sample z-test for this one since this problem is using proportions. Using a formula for a proportional one-sample z-test with your data included, we have: z = .1 - .15 -->test value (12/120) is .1) minus population value (.15) divided by &#...
*Wednesday, October 31, 2012 at 11:22am by MathGuru*

**statistics**

You can try a proportional one-sample z-test for the first problem since this problem is using proportions. Here's a few hints to get you started: Using a formula for a proportional one-sample z-test with your data included, we have: z = .63 - .50 -->test value (38/60 is ...
*Friday, December 27, 2013 at 2:22pm by MathGuru*

**statistics**

mortgage broker is offering home mortgages at a rate of 9.5%, but the broker is fearful that this value is higher than many others are charging. A sample of 40 mortgages filed in the county courthouse shows an average of 9.25% with a standard deviation of 8.61%. Does this ...
*Wednesday, June 19, 2013 at 5:09pm by Rald*

**Statistics**

Here are a few hints: 1. Use a one-sample z-test for both A and B, which is: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) 2. Find the critical or cutoff value to reject the null using a z-table for .05 level of ...
*Monday, November 15, 2010 at 5:34pm by MathGuru*

**statistics**

Try a one-sample z-test on this data: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) z = (49 - 50)/(5/√36) I'll let you finish the calculation. Check a z-table for your critical or cutoff value at .05 level of ...
*Tuesday, July 30, 2013 at 1:51pm by MathGuru*

**Chem**

A gas generator is constructed to collect the CO2(g) evolved from a reaction. during lab we set up the CO2 generator by placing 10ml of 3 M HCL in a 200mm test tube. then slide the 75mm test tube into the 200mm test tube without splashing any of the acid into the sample. The ...
*Wednesday, November 16, 2011 at 5:40pm by Ben*

**statistics**

In a recent study on gender differences in education, a sample of 7 boys had a mean score of 18.5 and a standard deviation of 4.1 on a Standardized Math Test. A sample of 11 girls had a mean score of 19.9 and a standard deviation of 3.6 on the same test. What is the t-...
*Sunday, March 24, 2013 at 1:31am by Alex*

**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**

Usually you use z-tests when sample sizes are large (n is greater than or equal to 30) whether or not you know the population standard deviation. If you do not know the population standard deviation and have a small sample (n < 30), then you can use t-tests. Therefore, try ...
*Monday, August 9, 2010 at 5:05pm by MathGuru*

**Statistics**

Use a one-sample z-test. Hypotheses: Ho: = 124 -->null hypothesis Ha: > 124 -->alternate hypothesis z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (125.50 - 124)/(2.25/√35) = ? ...
*Thursday, April 19, 2012 at 5:13pm by MathGuru*

**statistics**

Scores on a certain test are normally distributed with a variance of 14. A researcher wishes to estimate the mean score achieved by all adults on the test. Find the sample size needed to assure with 95% confidence that the sample mean will not differ from the population mean ...
*Monday, September 13, 2010 at 7:58pm by Sarah*

**Statistics p-value**

You can try a proportional one-sample z-test for this one since this problem is using proportions. Null hypothesis: Ho: p = .63 -->meaning: population proportion is equal to .63 Alternative hypothesis: Ha: p > .63 -->meaning: population proportion is greater than .63...
*Wednesday, October 30, 2013 at 5:10pm by MathGuru*

**Stat**

For the first part of this problem, you can try a z-test. You will need to calculate the sample mean before using the formula below: z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) Population mean = 172 Standard deviation...
*Thursday, April 21, 2011 at 2:57pm by MathGuru*

**statistics**

4. Suppose you administered an anxiety test to a large sample of people and obtained normally distributed scores with a mean of 45 and standard deviation of 4. Do not use web-calculator to answer the following questions. Instead, you need to use the Z distribution table in ...
*Monday, September 3, 2012 at 8:55pm by Edward*

**statistics**

You can try a proportional one-sample z-test for this one since this problem is using proportions. Using a formula for a proportional one-sample z-test with your data included, we have: z = .225 - .30 -->test value (45/200) is .225) minus population value (.30) divided by...
*Monday, November 19, 2012 at 3:29am by MathGuru*

**Statistics**

Try a one-sample z-test. Hypotheses: Ho: = 40 -->null hypothesis Ha: > 40 -->alternate hypothesis z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size) With your data: z = (43.5 - 40)/(8/√100) = ? Finish the ...
*Wednesday, April 4, 2012 at 4:38pm by MathGuru*

**Psychology/Statistics**

For each of the following samples that were given an experimental treatment test whether these samples represent populations that are different from the general population (a) a sample of 10 with a mean of 44, (b) a sample of 1 with a mean of 48. The general population of ...
*Friday, July 15, 2011 at 9:39pm by Dawn*

Pages: **1** | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | Next>>