Saturday

April 18, 2015

April 18, 2015

**Recent Homework Questions About Statistics**

**elementary statistics**

A statistics professor is used to having a variance in his class grades of no more than 100. He feels that his current group of students is different, and so he examines a random sample of midterm grades (listed below). At 0.05 alpha level can it be conculded that the variance...
*Saturday, November 30, 2013 at 7:44pm*

**statistics**

Ala rge fleet of cars is maintained with an average of 26 mpg. 50 recent trips displayed a mean of 25.02 mpg and standard deviation of 4.1 mpg. At the 5% level of significance, is their evidence the company has failed to keep their fuel goals? I did the math and got .03380315...
*Saturday, November 30, 2013 at 12:27pm*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*Saturday, November 30, 2013 at 1:50am*

**Statistics**

I have two coins: a quarter and a nickel. The quarter has a bias of 1/4 for heads, and the nickel has a bias of 2/3 for heads. I flip each coin 10 times. What is the probability that I observe exactly five heads total? Some explanation of the solution would be appreciated.
*Friday, November 29, 2013 at 11:04pm*

**Statistics**

Hello, my problem is I have a random sample of only 15 sales average is $115 with a known population standard deviation of $25.00. Obtain a 92% confidence interval and explain what your answer means. I am not sure what to do because the sample size is only 15. Thanks for your ...
*Friday, November 29, 2013 at 8:00pm*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*Friday, November 29, 2013 at 7:30pm*

**statistics**

In a distribution of sentence lengths in months like the following: 6, 12, 10, 18, 24, 360; which statistic would a researcher not want to report? a. standard deviation b. mean c. range d. raw numbers
*Friday, November 29, 2013 at 8:13am*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*Thursday, November 28, 2013 at 5:13pm*

**Probability and Statistics**

The proportion of adults living in a small town who are college graduates is estimated to be p = 0.6. To test this hypothesis, a random sample of 15 adults is selected. If the number of college graduates in the sample is anywhere from 6 to 12, we shall not reject the null ...
*Wednesday, November 27, 2013 at 11:34pm*

**Statistics**

A statistics professor plans her classes so carefully that the lengths of her class are uniformly distributed between 46.0 and 56.0 minutes. Find the probablity that given class period runs less than 51.75 minutes
*Wednesday, November 27, 2013 at 3:47am*

**Statistics**

A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study, 449 babies were born, and 250 of them were girls. Use the sample data with .01 significance level to test the claim that with this method, the probability of a baby being a...
*Tuesday, November 26, 2013 at 6:03pm*

**statistics**

A particular country has 55 total states. If the areas of 30 states are added and the sum is divided by 30, the result is 196,582 square kilometers. Determine whether this result is a statistic or a parameter and why.
*Tuesday, November 26, 2013 at 1:02pm*

**statistics**

With n=13 and p= 0.7, find the binomial probability p(9) by using a binomial probability table. If np> and nq> 5, also estimate the indicated probability by using the normal distribution as an approximation to the binomial, if np<5 or nq<5 then state that the ...
*Monday, November 25, 2013 at 9:36pm*

**Statistics**

An industrial psychologist has a stress test that is used to determine the amount of stress that managers are under. A value of 80 or higher indicates “high stress.” The industrial psychologist believes that the managers at a large, profitable pharmaceutical firm are...
*Monday, November 25, 2013 at 5:22pm*

**statistics**

In a study of caffeine and stress, college students indicate how many cups of coffee they drink per day and their stress level on a scale of 1-10. The data appear below. Number of Cups of Coffee Stress Level 3 5 2 3 4 3 6 9 5 4 1 2 7 10 3 5 = 3.88 X= 5.13 s = 2.03 s = 2.90 ...
*Monday, November 25, 2013 at 3:36pm*

**statistics psy/315**

Based on the information given for each of the following studies, decide whether to reject the null hypothesis.For each, give (a) the Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected(b) the Z score on the comparison ...
*Monday, November 25, 2013 at 11:12am*

**statistics**

A clinical trial tests a method designed to increase the probability of conceiving a girl. In a study 306 babies were born, and 174 of them were girls. the sample data with a 0.01 significance level to test the claim that with this method, the probability of being a girl is ...
*Monday, November 25, 2013 at 10:25am*

**Statistics**

n two separate studies, the actual difference between the means of a treated group and an untreated group is 3 points. However, in one study, the ÏƒM1-M2 is very large and so the 3 points is not found to be significant. In the other study, the ÏƒM1-M2 is ...
*Monday, November 25, 2013 at 7:18am*

**statistics**

how would you tell deviations from normality by looking at a box plot?
*Sunday, November 24, 2013 at 7:11pm*

**statistics**

how would you tell deviations from normality by looking at a box plot?
*Sunday, November 24, 2013 at 7:08pm*

**statistics**

what makes a probability plot non-normal? I would think outliers are one of them, but what else?
*Sunday, November 24, 2013 at 7:06pm*

**Statistics**

Given the following information, determine the 68.3 percent, 95.5 percent, and 99.7 percent confidence intervals. overbar above X equals 4.33 comma SE sub m equals 3 I would appreciate it extremely if someone would help me figure this out. I honestly have no idea how to do ...
*Sunday, November 24, 2013 at 6:33pm*

**statistics**

Typing speeds among college students are normally distributed with a mean of 60 words, and a standard deviation of 10 words. determine the typing speed that separates the top 6% typists from the rest.
*Sunday, November 24, 2013 at 3:55pm*

**statistics**

1. A professor measured the time (in seconds) required to catch a falling meter stick for 19 randomly selected students’ dominant and non-dominant hand. The professor claims that the reaction time in an individual’s dominant hand is less than the reaction time in ...
*Sunday, November 24, 2013 at 3:33pm*

**Statistics**

142 out of 507 people were right. Calculate a 95% confidence interval for the proportion of the entire population that could be right. I did some of the work …Please help. I am getting .0199 SD =sqt(.28(1-.28)/506 = .0119 so .28 +/- .0119 so I could say that with 95% ...
*Sunday, November 24, 2013 at 3:08pm*

**Statistics**

142 out of 507 people were right. Calculate a 95% confidence interval for the proportion of the entire population that could be right. I did some of the work and got .72...don't know what to do with this? Please help.
*Sunday, November 24, 2013 at 1:45pm*

**Statistics**

A sample of 11 observations taken from a normally distributed population produced the following data. −7.1 10.3 8.7 −3.6 −6.0 −7.5 5.2 3.7 9.8 −4.4 6.4 a) What is the point estimate of μ? b) Make a 95% confidence interval for μ. c) What ...
*Sunday, November 24, 2013 at 12:25pm*

**Statistics**

Many dairy cows now receive injections of BST, a hormone intended to spur greater milk production. A group of 53 Jersey cows increased average milk production from 43 to 52 pounds per day, with a standard deviation of 4.8 lbs. Is this evidence that the hormone maybe effective ...
*Sunday, November 24, 2013 at 9:14am*

**statistics**

For the past 20 years, the high temperature on April 15th has averaged = 62 degrees with a standard deviation of = 12. Last year, the high temperature was 68 degrees. Based on this information, which of the following best describes last year's temperature...
*Sunday, November 24, 2013 at 2:42am*

**Statistics**

Exercise 8.92 Tony's Pizza guarantees all pizza deliveries within 30 minutes of the placement of orders. An agency wants to estimate the proportion of all pizzas delivered within 30 minutes by Tony's. What is the most conservative estimate of the sample size that would...
*Saturday, November 23, 2013 at 6:10pm*

**Statistics**

Tony's Pizza guarantees all pizza deliveries within 30 minutes of the placement of orders. An agency wants to estimate the proportion of all pizzas delivered within 30 minutes by Tony's. What is the most conservative estimate of the sample size that would limit the ...
*Saturday, November 23, 2013 at 6:08pm*

**statistics**

If the average commute time is 10.9 miles, but the average is actually the mean of a sample of 300 commuters and the sample standard deviation is 6.2 miles Estimate the true mean commute distance using 99% confidence level.
*Saturday, November 23, 2013 at 3:00pm*

**Statistics**

125/500 women soda drinkers indicate they drink diet soda. At the .01 level, does this evidence indicate that more than 20% of the women soda drinkers drink diet soda? Determine and explain the P-value please. I have the numbers...just cannot explain. Please help.
*Saturday, November 23, 2013 at 2:51pm*

**statistics**

Failing to reject the null hypothesis when it is false is a Type II Error. T or F, and why or why not?
*Saturday, November 23, 2013 at 10:30am*

**statistics**

IQ scores were obtained from randomly selected couples.For 20 such pairs of people, the linear correlation coefficient is 0.881 and the equation of the regression line is y= -6.93+ 10.8x, where x represents the IQ score of the husband. Also, the 20x values have a mean of 105....
*Saturday, November 23, 2013 at 8:42am*

**statistics**

Assume that thermometer readings are normally distributed with a mean of 0.0 and a standard deviation of 1,00. the thermometer is randomly selected and tested. For the case below, draw a sketch , and find the probability of the reading The given values in Celsius degrees) ...
*Friday, November 22, 2013 at 2:09pm*

**statistics**

Is there a significant difference between first year post college incomes of graduates from public versus private institutions? Provide the IV, DV, and best method of analysi
*Thursday, November 21, 2013 at 9:41pm*

**Statistics**

Many dairy cows now receive injections of BST, a hormone intended to spur greater milk production. A group of 53 Jersey cows increased average milk production from 43 to 52 pounds per day, with a standard deviation of 4.8 lbs. Is this evidence that the hormone maybe effective ...
*Thursday, November 21, 2013 at 7:31pm*

**Statistics**

If the cases selected for one sample have no influence upon the cases selected for a second sample, then the samples are said to be: A) independent B) inconsistent C) dependent D) consistent A
*Thursday, November 21, 2013 at 7:27pm*

**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*

**Statistics**

A researcher wished to test the effect of the addition of extra calcium to yogurt on the "tastiness" of yogurt. Two different yogurts, one with extra calcium and one without the added calcium, were created from the same batch of yogurt. A group of 84 adult volunteers...
*Thursday, November 21, 2013 at 6:39pm*

**statistics 201**

A firm hires a pool of financial consultants to discuss portfolio recommendations with its clients. The CEO believes that another financial consultant should be hired if the average phone consultation exceeds 350 seconds. A random sample of 100 phone calls revealed a mean of ...
*Thursday, November 21, 2013 at 2:48pm*

**Statistics**

The standard deviation for a population is σ = 15.3. A sample of 36 observations selected from this population gave a mean equal to 74.8. a) Make a 90% confidence interval for μ b) Construct a 95% confidence interval for μ. c) Determine a 99% confidence interval...
*Thursday, November 21, 2013 at 11:11am*

**Statistics**

Given the following null hypothesis, give an example of a Type II error. Ho: There is no difference in the level of understanding of this chapter between students who have previously taken a statistics course and students who have not previously takn a stastics course.
*Thursday, November 21, 2013 at 9:55am*

**Statistics**

given the following null hypothesis, give an example of a type I error. Ho: There is no difference between the number of males or females who go to their primary care physician for an annual exam.
*Thursday, November 21, 2013 at 9:53am*

**Statistics**

given the following information, determine the 68.3 percent, 95.5 percent, and 99.7 percent confidence intervals. Mean = 4.33, standard error of the mean =3
*Thursday, November 21, 2013 at 9:46am*

**Statistics**

Create a null hypothesis for the following research questions: a. What are the differences between emergency room shifts on medication errors? b. On a clinical trial of a new drug, what will be the effects over a currently used drug?
*Thursday, November 21, 2013 at 9:41am*

**statistics**

conduct a study on support of ban on smartphones in class. 68/87 said yes. How large of a sample is needed to be sure the margin of error +/- 3.5% with 99% confidence. I know this is estimation...but I am not sure how to go about solving this problem.
*Wednesday, November 20, 2013 at 9:38pm*

**statistics**

I am conducting a study on support of ban on smartphones in class. 68/87 said yes to the ban. How large of a sample is needed to be sure the margin of error +/- 3.5% with 99% confidence. I know this is estimation...but I am not sure how to go about solving this problem.
*Wednesday, November 20, 2013 at 9:19pm*

**Statistics**

Most people are definitely dominant on one side of their body - either right or left. For some sports being able to use both sides is an advantage, such as batting in baseball or softball. In order to determine if there is a difference in strength between the dominant and non-...
*Wednesday, November 20, 2013 at 8:03pm*

**Statistics**

A packing company investigates a national training consultant in hopes of improving productivity on the packing line. The national consultant agrees to work with 18 employees, collecting productivity data for each employee before the training program and after the training ...
*Wednesday, November 20, 2013 at 8:02pm*

**Statistics**

When comparing two samples that are independent of one another, we use the two-sample t-test. A) True B) False 5. Using paired differences helps to reduce the variation. A) True B) False Both are True?
*Wednesday, November 20, 2013 at 4:48pm*

**Statistics**

Create a null hypothesis for the following research questions: a. What are the differences between emergency room shifts on medication errors? b. On a clinical trial of a new drug, what will be the effects over a currently used drug?
*Wednesday, November 20, 2013 at 9:29am*

**Statistics**

How could you reword these research hypotheses to null hypotheses? a. Smoking during pregnancy increase the risk of a child being born prematurely. b. Regular exercises in older adults decreases blood pressure levels.
*Wednesday, November 20, 2013 at 9:29am*

**Statistics**

Given the following p values which would be considered more significant? a) p ≤ 0.3 b) p ≤ 0.02 c) p ≤ 0.25
*Wednesday, November 20, 2013 at 9:28am*

**Statistics**

Battery manufacturers compete on the basis of the amount of time their products last in cameras and toys. A manufacturer of alkaline batteries has observed that it's batteries last for an average of 26 hours when used in a toy racing car. The amount of time is normally ...
*Wednesday, November 20, 2013 at 4:23am*

**statistics**

You randomly choose 16 unfurnished one-bedroom apartments from a large number of advertisements in your local newspaper. You calculate that their mean monthly rent is $613 and their standard deviation is $96. Does this SRS give good reason to believe that the mean rent of all ...
*Tuesday, November 19, 2013 at 8:58pm*

**statistics**

A group of 49 randomly selected construction workers has a mean age of 22.4 years with a standard deviation of 3.8. According to a recent survey, the mean age should be mu=21.9. Test this hypothesis by constructing a 98% confidence interval for the population mean.
*Tuesday, November 19, 2013 at 6:31pm*

**statistics**

In a study designed to test the effectiveness of magnets for treating back pain, 40 patients were given a treatment with magnets and also a sham treatment without magnets. Pain was measured using a scale from 0 to 100. After given the magnet treatments, the 40 patients had ...
*Tuesday, November 19, 2013 at 6:20pm*

**statistics**

A data set includes 108 body temperatures of healthy adult humans for which x is 98.2 degrees and s is 0.64 degrees. What is the best point estimate of the mean body temperature of all healthy humans?
*Tuesday, November 19, 2013 at 5:57pm*

**statistics**

A study of the time spent shopping in a supermarket for a market basket of 20 specific items showed an approximately uniform distribution between 20 minutes and 40 minutes. What is the probability that the shopping rime will be a. Between 25 and 30 minutes? b. less than 35 ...
*Tuesday, November 19, 2013 at 10:54am*

**Statistics**

given the following p values which would be considered more significant? a) p ≤ 0.3 b) p ≤ 0.02 c) p ≤ 0.25
*Tuesday, November 19, 2013 at 10:44am*

**Statistics**

How could you reword these research hypotheses to null hypotheses? a. Smoking during pregnancy increase the risk of a child being born prematurely. b. Regular exercises in older adults decreases blood pressure levels.
*Tuesday, November 19, 2013 at 10:37am*

**Statistics**

Create a null hypothesis for the following research questions: a. What are the differences between emergency room shifts on medication errors? b. On a clinical trial of a new drug, what will be the effects over a currently used drug?
*Tuesday, November 19, 2013 at 10:34am*

**statistics**

A data set includes body temperatures of healthy adult humans for which x= 98.2 and s=0.64 F. Complete parts a) and b) below a) what is the best point estimate of the mean body temperature of all healthy humans? The best point estimate is F. b) Using the sample statistics, ...
*Tuesday, November 19, 2013 at 5:34am*

**Statistics, epidemio**

Im a medical student and i need to evaluate the Association between depression to cardiovascular disease. 1. what Type of Research Studies makes sense to do? 2.Design (Study period, epidemiological approach...) 2. Who are the participants in study and how will be selected? (...
*Tuesday, November 19, 2013 at 5:16am*

**statistics**

2. Betty, an employee of Shining Sun Daycare Center, read an article in Healthy Child Magazine saying that the average 3-year-old child is 37 in. tall. Betty works with 3-year-olds at Shining Sun, so later that week, she measured the height of each child who had just turned or...
*Monday, November 18, 2013 at 11:25pm*

**statistics**

Assume that a test is given to a large number of people but we do not yet know their scores or the shape of the score distribution. Can we be sure that the sampling distribution of the mean for this test will be normally distributed? Why or why not?
*Monday, November 18, 2013 at 11:00pm*

**statistics**

Ina study designed to test the effectiveness magnets for treating back pain, 35 patients were given a treatment with magnets and also a sham treatment without magnets. Pain was measured using a scale from 0(no pain) to 100(extreme pain) after the given magnet treatments, the ...
*Monday, November 18, 2013 at 9:48pm*

**statistics**

Age at onset of dementia was determined for a sample of adults between the ages of 60 and 75. For 15 subjects, the results were ÓX = 1008, and Ó(X-M)2 = 140.4. Use this information to answer the following:
*Monday, November 18, 2013 at 9:18pm*

**Statistics**

Assume that a test is given to a large number of people but we do not yet know their scores or the shape of the score distribution. Can we be sure that the sampling distribution of the mean for this test will be normally distributed? Why or why not?
*Monday, November 18, 2013 at 8:49pm*

**Statistics**

SAT scores are normally distributed with a mean of 500 and a standard deviation of 100. Using the formula for ÏƒM, what will ÏƒM 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*

**Statistics**

A VP of manufacturing claims that more than 3% of items produced using a certain assembly line are is defective. A random sample of 100 items from the assembly line had 4 defectives. At the 5% level of significance, which of the following would be part of the standardized ...
*Monday, November 18, 2013 at 3:16pm*

**Statistics**

A recent Gallup Poll dealt with the proportion of Canadians who favoured the various Prime Ministers. It found that only Pierre Trudeau did quite well, of all Prime Ministers in recent memory, and that the proportion favouring Brian Mulroney is quite low. A newspaper article ...
*Monday, November 18, 2013 at 3:15pm*

**Statistics**

A VP of manufacturing claims that more than 3% of items produced using a certain assembly line are is defective. A random sample of 100 items from the assembly line had 4 defectives. At the 5% level of significance, which of the following would be part of the standardized ...
*Monday, November 18, 2013 at 3:14pm*

**statistics**

The eruption height and the time interval after eruption of a geyser were measured and shown below. Height(x) 115 120 120 130 140 110 140 100 Interval after(y) 59 64 68 71 75 56 73 54
*Monday, November 18, 2013 at 8:35am*

**statistics**

Consider an upper-tail test of hypothesis for the difference in two population means. The sample data from the first population is: n = 50, x-bar = 110, s = 10. The sample data from the second population is: n = 75, x-bar = unknown, s = 11. We conclude the alternative ...
*Sunday, November 17, 2013 at 11:01pm*

**statistics**

A random sample of 100 students from a high school was selected. If a 98% confidence interval estimate for the mean age of students is calculated to be 14.2511 to 14.9489, then the standard deviation of the sample mean is?
*Sunday, November 17, 2013 at 10:54pm*

**statistics**

A management consultant has analysed a random sample of 40 large firms in order to investigate the mean annual salary of sales managers. She has constructed the following 90% confidence interval for the population mean annual salary: $45,382 to $48,618. In testing the ...
*Sunday, November 17, 2013 at 10:53pm*

**Statistics**

Of 500 randomly selected people in new york city, 210 people had O+ blood. "58 percent of the people in NYC do not have type O+ blood" Is the statement descriptive statistics or inferential statistics?
*Sunday, November 17, 2013 at 5:08pm*

**statistics**

How large a sample would be needed to form a 90% confidence interval for the mean nicotine content of a brand of cigarettes if the nicotine content has a normal distribution with sigma equal to 8.5 mg and the width of the interval (the length of the confidence interval) equal ...
*Sunday, November 17, 2013 at 12:56pm*

**Statistics**

A credit manager has chosen a sample of size 2,164 to estimate the mean balance of credit accounts to within $0.50. A pilot study of 50 accounts had a mean of $1,219 and a variance of 100. The level of confidence of the interval is: 90% ? 95% ? 98% ? 99% ?
*Sunday, November 17, 2013 at 12:25pm*

**statistics**

Randomly selected students participated in an experiment to test their ability to determine when one minute(or sixty seconds) has passed. Forty students yielded a sample mean of 61.8 seconds. Assuming that o= 11.7 seconds, Construct and interpret a 99% confidence interval ...
*Sunday, November 17, 2013 at 12:19pm*

**statistics**

A fertilizer mixing machine is set to give 4 kg of nitrate for every quintal bag of fertilizers. Five 100 kg bags are examined. The percentages of nitrate are: 2, 6, 4, 3, 1. is there reason to believe that the machine is defective?
*Sunday, November 17, 2013 at 7:41am*

**Statistics**

On the last three Friday evening, City hospital diagnosed a number of heroin overdoses. There were four on 1/14/20xx, two on 1/21/20xx, and six on 1/28/20xx. a) "City Hospital averaged four herion overdoses in their ER for the last three Firday evenings" Is the ...
*Saturday, November 16, 2013 at 10:44pm*

**Statistics**

1. of 500 randomly selected people in new york city, 210 people had O+ blood. a) "42 percent of the people in NYC have O+ blood" Is the statement descriptive statistics or inferential statistics? b) "58 percent of the people in NYC do not have type O+ blood"...
*Saturday, November 16, 2013 at 10:42pm*

**Statistics**

In the following question, identify which choices would be considered inferential statistics and which would be considered inferential statistics. 1. of 500 randomly selected people in new york city, 210 people had O+ blood. a) "42 percent of the people in NYC have O+ ...
*Saturday, November 16, 2013 at 8:55pm*

**Statistics**

In the following question, identify which choices would be considered inferential statistics and which would be considered inferential statistics. On the last three Friday evening, City hospital diagnosed a number of heroin overdoses. There were four on 1/14/20xx, two on 1/21/...
*Saturday, November 16, 2013 at 8:53pm*

**Statistics**

A credit manager has chosen a sample of size 2,164 to estimate the mean balance of credit accounts to within $0.50. A pilot study of 50 accounts had a mean of $1,219 and a variance of 100. The level of confidence of the interval is: 90% 95% 98% 99%
*Saturday, November 16, 2013 at 7:11pm*

**Statistics**

The mean length of the first 20 space shuttle flights was about 7 days with a standard deviation of about 2 days. Using Chebychev's theorem, at least how many of the flights lasted between 3 and 11 days.
*Saturday, November 16, 2013 at 1:26pm*

**Statistics**

The following table shows a frequency distribution of patients with colon cancer treated at Community Hospital. Compute the proportion of patients in each category. Community Hospital Ages of Patients with Colon Cancer Annual Statistics, 20XX Age No. of Patients Proportion &#...
*Saturday, November 16, 2013 at 10:37am*

**stastics**

Assume that a random sample is used to estimate a population proportion p. Find the margin of error E corresponds to the given statistics and confidence level. 90% confidence, the sample size is 1457, of which 30% are successes.
*Saturday, November 16, 2013 at 3:03am*

**Statistics**

A survey was conducted to determine if there is a difference in gasoline mileage for two types of trucks, truck A and truck B. A random sample was taken for each model of truck, and the mean gasoline mileage, in miles per gallon, was calculated. Identify the appropriate ...
*Friday, November 15, 2013 at 7:32pm*

**Statistics**

To do inferential procedures comparing two proportions, we need another variance formula (our ruler). This formula is based on what principle? A) The variance of the difference of two statistics is the difference of the variances of each statistic. B) The variance of the ...
*Friday, November 15, 2013 at 7:30pm*

**statistics**

Use the given information to find the minimum sample size required to estimate an unknown population mean u. How many adults must be randomly selected to estimate the mean FICO (credit rating)score of working adults in a country? We want 95% confidence that the sample mean is ...
*Friday, November 15, 2013 at 4:48pm*

**statistics**

an airline has a policy of booking as many as 24 person on an airplane that can seat only 23 (past studies have revealed that only 94 % of booked passengers actually arrive for the flight) find the probability that if the airline booked 24 persons, not enough seats will be ...
*Friday, November 15, 2013 at 11:14am*

**Statistics**

In the following two questions, identify which choices would be considered inferential statistics and which would be considered inferential statistics. 1. of 500 randomly selected people in new york city, 210 people had O+ blood. a) "42 percent of the people in NYC have O...
*Friday, November 15, 2013 at 9:45am*

**Statistics**

How do the 3rd grade boys’ weight in Principal Ben’s school compare to the national average (mean weight = 90, sd =15)? Provide the IV, DV, and best method of analysis.
*Thursday, November 14, 2013 at 11:20pm*

**statistics**

Find the mean, the median, and the mode for the following data. 21 21 22 22 22 26 34 Mean 335.1 rounded to 335, median 22, mode is 22
*Thursday, November 14, 2013 at 11:00pm*

**statistics**

I have to find mean, median and mode did I do this right? 21,21,22,22,22,26,34
*Thursday, November 14, 2013 at 10:57pm*