Monday

May 25, 2015

May 25, 2015

**statistics**

Which data provide the answer to the question: “How frequently can a student at Eureka College be expected to study more than three hours a day?” A. Of 100 students surveyed, 43 reported that they study at least three hours a day twice a week. B. Of 100 students ...
*Friday, April 10, 2015 at 10:45am*

**statistics**

A poll of 700 persons attending the Taste of Chicago showed that 455 persons, 65% of the sample, believed that the food was overpriced. It is estimated that 1,250,000 persons attend the Taste. Statistics suggest that, although 65% plus or minus 5% of attendees believe that the...
*Friday, April 10, 2015 at 10:42am*

**social studies**

A poll of 700 persons attending the Taste of Chicago showed that 455 persons, 65% of the sample, believed that the food was overpriced. It is estimated that 1,250,000 persons attend the Taste. Statistics suggest that, although 65% plus or minus 5% of attendees believe that the...
*Friday, April 10, 2015 at 9:47am*

**statistics**

A U.S. government report stated that, “With bank interest rates around 1.0%, 8% of wage earners believe it worthwhile to keep money in a savings account. However, at 3.0% interest, 36% of wage earners believe it worthwhile to keep money in a savings account. The margin of...
*Friday, April 10, 2015 at 9:22am*

**statistics**

A nutritionist wants to conduct a study to validate the efficacy of an herb as an aid in weight loss. She randomly assigns half of a group of overweight persons to a treatment group who are given the herb with instructions for its use and a planned diet for six weeks. The ...
*Friday, April 10, 2015 at 9:19am*

**english**

About 200 years ago the Cherokee Indians were one tribe, or "Indian Nation" that lived in the southeast part of what is now the United States. During the 1830's and 1840's, the period covered by the Indian Removal Act, (1) many Cherokees were moved west to a...
*Thursday, April 9, 2015 at 1:06pm*

**Statistics**

A Today/CNN/Gallup Poll of 1015 adults found that 13% approved of the job Congress was doing in 1995. Find the 95% confidence interval of the true proportion of adults who feel this way.
*Wednesday, April 8, 2015 at 10:59pm*

**statistics**

last year houston hospital averaged 98 births a month with a standard deviation of 6 january reported 107 birhts. how does the number of birhts in january compare to the average
*Wednesday, April 8, 2015 at 9:42pm*

**statistics**

Suppose that your studying tine is unifornily distribution between 4 pm and 10pm what is the probability that will study afterb8 pm
*Wednesday, April 8, 2015 at 11:03am*

**statistics**

The average number of houses sold by a company is 2 houses per day what is probability that's exactly 3 houses will be sold in one week
*Wednesday, April 8, 2015 at 10:59am*

**business statistics**

pkg1 pkg2 215 148 89 70 367 292 find the relative frequency of occurrence approach to determine the probability that a tube of toothpaste sold had packaging style 1
*Monday, April 6, 2015 at 5:13pm*

**Writing Skills, Part 3**

6. You have found an article in the Readers' Guide that you want to locate. What information would be least important in finding it? A. Subject heading B. Volume and page numbers C. Author's name D. Title of the article Student Answer: B Answer: Incorrect Reference: 7...
*Sunday, April 5, 2015 at 7:33pm*

**Statistics**

Find the margin of error for a 95% confidence interval for estimating the population mean when the sample standard deviation equals 100, with a sample size of (i) 400, (ii) 1600. What is the effect of the sample size? (b) Find the margin of error for estimating the population ...
*Sunday, April 5, 2015 at 1:03pm*

**statistics**

A test consist of 10 multiple choice questions, each with five possible answers, one of which is correct. To past the test a student must get 60% or better
*Saturday, April 4, 2015 at 11:37pm*

**Statistics**

Find the margin of error for a 95% confidence interval for estimating the population mean when the sample standard deviation equals 100, with a sample size of (i) 400, (ii) 1600. What is the effect of the sample size? (b) Find the margin of error for estimating the population...
*Saturday, April 4, 2015 at 3:09pm*

**Statistics**

If the average home cost $100,000, with a standard deviation of $15,000, what would a home on the 20th percentile rank cost?
*Friday, April 3, 2015 at 12:03pm*

**Statistics **

A sample of 53 night-school students' ages is obtained in order to estimate the mean age of night-school students. = 25.7 years. The population variance is 12. (a) Give a point estimate for mu. (b) Find the 95% confidence interval for mu (lower and upper limit). (c) Find ...
*Thursday, April 2, 2015 at 7:45pm*

**Statistics **

By measuring the amount of time it takes a component of a product to move from one workstation to the next, an engineer has estimated that the standard deviation is 6 seconds. (a) How many measurements should be made to be 90% certain that the maximum error of estimation will...
*Thursday, April 2, 2015 at 7:42pm*

**Statistics**

How large a sample should be taken if the population mean is to be estimated with 90% confidence to within $75? The population has a standard deviation of $892. So far I have n= (.2)(5)^2, but I don't think that's right....
*Thursday, April 2, 2015 at 7:39pm*

**statistics**

Let X and Y be independent random variables, each uniformly distributed on the interval [0,1]. Let Z=max{X,Y}. Find the PDF of Z. Express your answer in terms of z using standard notation . For 0<z<1, fZ(z)= 1 - unanswered 1 Let Z=max{2X,Y}. Find the PDF of Z. Express ...
*Wednesday, April 1, 2015 at 3:58pm*

**statistics**

A brewery's filling machine is adjusted to fill bottles with a mean of 31.9 oz. of ale and a variance of 0.004. Periodically, a bottle is checked and the amount of ale noted. (a) Assuming the amount of fill is normally distributed, what is the probability that the next ...
*Tuesday, March 31, 2015 at 8:29pm*

**statistics**

What is the difference between alpha level and critical values?? Does the alpha level just help determine the critical value?
*Tuesday, March 31, 2015 at 8:05pm*

**statistics **

If the null hypothesis is rejected at the .01 alpha level, it will be rejected at the .05 alpha level. Is this correct?
*Tuesday, March 31, 2015 at 6:21pm*

**Statistics**

In the past year, Jack's Pizaa Resturant grossed more than $1500 a day for about 83% of its business days. Suppose 8 days are randomly selected, approximate the probablity that exactly 6 days will gross more than $1500 in a day.
*Tuesday, March 31, 2015 at 12:40pm*

**Math, statistics**

Problem 1: The PDF of exp(X) (6/6 points) Let X be a random variable with PDF fX. Find the PDF of the random variable Y=eX for each of the following cases: For general fX, when y>0, fY(y)= Solution: f_x(ln(y))/y When fX(x) = {1/3,0,if −2<x≤1,otherwise, we ...
*Tuesday, March 31, 2015 at 8:34am*

**statistics**

1. Suppose the estimate of a proportion of a normal population is to be within 0.05 using the 95% confidence level. How large a sample is required if: a. It is known from previous studies that p = 0.3? b. There is no prior knowledge of p? 2. Each of the following is a large-...
*Tuesday, March 31, 2015 at 8:15am*

**Statistics**

It is pretty common across most schools to find the grades at the MBA level divided between A's and B's. As such, you expect the mean GPA to be around 3.50. Using the sample of 200 MBA students, conduct a one-sample hypothesis test to determine if the mean GPA is ...
*Tuesday, March 31, 2015 at 6:16am*

**Statistics**

1 39 63 wind speed (km h ) –1 Measurements of wind speed on a certain island were taken over a period of one year. A box-andwhisker plot of the data obtained is displayed above, and the values of the quartiles are as shown. It is suggested that wind speed can be modelled ...
*Monday, March 30, 2015 at 5:48pm*

**Marketing reserch**

a marketing researcher analyzing the fast food industry noticed the following restaurant in Cali was 3.30 with a standard deviation of .40. yet in Georgia the average amount spent at a fast food restaurant was 3.25 with a standard deviation of .10. what do these statistics ...
*Monday, March 30, 2015 at 12:16pm*

**statistics**

63% of men consider themselves baseball fans. You randomly select 10 and ask if he consider him self a baseball fan. Find the probability that the number who consider themselves baseball fans is (a) exactly 8, (b) at least (8) less than (8)
*Monday, March 30, 2015 at 5:49am*

**Statistics**

College officials want to estimate the percentage of students who carry a gun, knife, or other such weapon. How many randomly selected students must be surveyed in order to be 94% confident that the sample percentage has a margin of error of 2 percentage points?
*Sunday, March 29, 2015 at 8:40pm*

**statistics**

A recent survey showed that among 675 randomly selected subjects who completed 4 years of college, 138 smoke and 537 do not smoke. Determine a 95% confidence interval for the true proportion of the given population that smokes.
*Sunday, March 29, 2015 at 8:09pm*

**statistics**

A simple random sample of a size n is drawn from a population that is normally distributed. The sample mean, x is found to be 110, and the sample standard deviation, s, is found to be 10. A- Construct a 95% confidence interval about u if the sample size, n, is 17
*Sunday, March 29, 2015 at 6:25pm*

**statistics**

a repair shop believes that people travel more than 3500 miles between oil changes a random sample of 8 cars getting an oil change has average distance of 3375 standard deviation of 225 miles with alpha 0.05 is there enough evidence to support the shops claim
*Sunday, March 29, 2015 at 1:38am*

**Statistics**

The percentage of various colors are different for the "peanut" variety of M&M's candies, as reported on the Mars, Incorporated website. Brown: 12% Yellow: 15% Red: 12% Blue: 23% Orange: 23% Green: 15% A 14-ounce bag of peanut M&M's is randomly selected and ...
*Saturday, March 28, 2015 at 11:24pm*

**statistics**

If I selected one player at random what would be the probability of an NBA player in the Eastern conference being less than 6 feet tall? First calculate the z-score and then use the standard normal table to find the probability.
*Saturday, March 28, 2015 at 3:41pm*

**math**

a statistics professor plans class so carefully that the lengths of his classes are uniformly distributed between 45.0 and 55.0 minutes. find the probability that a given class period runs greater than 50.75 minutes? find the probability of selecting a class that runs greater ...
*Saturday, March 28, 2015 at 1:32am*

**statistic**

A statistics quiz consists of 10 multiple questions. There are four choices for each question. One student is unprepared and decides to guess the answers to every question. Assuming 70% is a passing grade, find the probability that the student will pass the quiz.
*Saturday, March 28, 2015 at 1:28am*

**statistics**

Consider the test of hypothesis for the equality of two population means. The sample data from the first population is: n = 10, x-bar = 52.4, s = 5. The sample data from the second population is: n = 8, x-bar = 48.2, s = 6. Both variables are normally distributed and the ...
*Friday, March 27, 2015 at 9:26am*

**statistics**

A test of hypothesis is performed to determine whether the proportion of Montrealers (population 1) who want the decriminalization of marijuana is greater than the proportion of Torontonians (population 2) who want decriminalization of marijuana. A random sample of 115 ...
*Friday, March 27, 2015 at 9:25am*

**statistics **

A random sample of 150 investment bankers (population 1) had thirty percent who expressed dissatisfaction with their choice of career. A random sample of 200 financial analysts (population 2) had forty-two percent who expressed dissatisfaction. In testing the hypothesis that a...
*Friday, March 27, 2015 at 9:25am*

**statistics**

The Vancouver Chamber of Commerce claims that the mean cost of hotels in the downtown area of the city is less than in Edmonton. A random sample of 50 hotels in Vancouver (population 1) had a mean nightly rate of $109 with a standard deviation of $15. An independent sample of ...
*Friday, March 27, 2015 at 9:25am*

**statistics **

Which of the following statements are true? (A) In testing the hypothesis for the equality of two population proportions, the acceptance region for the null hypothesis will be wider than the confidence interval for two population proportions, assuming the same value of alpha...
*Friday, March 27, 2015 at 9:24am*

**statistics **

A comparison of the last year's (Population 1) versus the current year's (Population 2) shipments (in thousands of dollars) for each of six Canadian exporters is given as follows: (4.34, 4.77), (5.89, 5.16), (2.52, 2.73), (3.91, 4.39), (4.99, 5.25), (3.24, 3.80). It is...
*Friday, March 27, 2015 at 9:24am*

**statistics **

A VP of manufacturing claims that no more than 3% of items produced using a certain assembly line are defective. A random sample of 100 items from the assembly line had 5 defectives. At the 5% level of significance, which of the following would be part of the standardized ...
*Friday, March 27, 2015 at 9:23am*

**statistics **

The Dean of a university claims that no more than 10% of the students drop out of university. She chooses a random sample of 500 students and decides that she will accept the claim only if no more than 25 of the 500 students drop out of university. In fact her claim is true - ...
*Friday, March 27, 2015 at 9:23am*

**statistics **

Which of the following statements are false? (A) The t-distribution should always be used when n is small. (B) A test of hypothesis is found to have a p-value of .0682. Then one should conclude H1 if the level of significance is 10% and conclude Ho if the level of significance...
*Friday, March 27, 2015 at 9:22am*

**statistics **

A study is to be conducted to determine whether the mean cost of repairing a car is more than $500. A random sample of 100 repairs is selected and the following decision rule is constructed: conclude the null hypothesis if the sample mean is less than or equal to $515, ...
*Friday, March 27, 2015 at 9:22am*

**statistics**

A sample of 50 items is selected to determine whether or not to accept the hypothesis that a population means differs from a value of 20. The sample mean and standard deviation are 18 and 7, respectively. The null hypothesis is not rejected, which of the following is a ...
*Friday, March 27, 2015 at 9:21am*

**math/stats**

Which of the following statements are true? (A) In a two-tail test of hypothesis for a population mean the decision rule is to reject H0 if the test statistic lies outside of the action limits. (B) A statistical test of hypothesis is performed under the assumption that the ...
*Friday, March 27, 2015 at 9:19am*

**statistics**

a local content center reports that it has been experiencing a 15% rate of no shows on advanced reservations. Among 150 advanced reservations find the probability that there will be fewer than 20 no shows round the standard deviation to three decimal to work the problem
*Thursday, March 26, 2015 at 5:13pm*

**Business statistics**

5. An Aspirin manufacturer fills bottles by weight rather than by count. Since each bottle should contain 100 tablets, the average weight per tablet should be 5 grains. Each of 100 tablets taken from a large lot is weighed, resulting in a sample average weight per tablet of 4....
*Wednesday, March 25, 2015 at 3:21pm*

**Business statistics**

4. A study of the ability of individuals to walk in a straight line (“Can We Really Walk Straight?”, Amer. J. of Physical Anthro., 1992:19-27) reported the accompanying data on cadence (strides per second) for a sample of 20 randomly selected individuals. 0.95 0.82 0...
*Wednesday, March 25, 2015 at 3:20pm*

**Business statistics**

3. Determine the t-critical value for a two-sided confidence interval in each of the following situations. a. Confidence level = 95%, df = 15 b. Confidence level = 99%, n = 5. c. Confidence level = 95%, n = 15 d. Significance level = 0.01, df = 37
*Wednesday, March 25, 2015 at 3:19pm*

**Business statistics**

2. Each of the following is a large-sample confidence interval for μ, the mean resonance frequency (HZ) for all tennis rackets of a certain type. (114.4, 115.6), (114.1, 115.9) a. What is the value of the sample mean resonance frequency? b. Both intervals were calculated ...
*Wednesday, March 25, 2015 at 2:57pm*

**Business statistics**

1. Suppose the estimate of a proportion of a normal population is to be within 0.05 using the 95% confidence level. How large a sample is required if: a. It is known from previous studies that p = 0.3? b. There is no prior knowledge of p?
*Wednesday, March 25, 2015 at 2:56pm*

**statistics**

4.The College Boards, which are administered each year to many thousands of high school students, are scored so as to yield a mean of 500 and standard deviation of 100. These scores are close to be normally distributed. a. What percentage of the scores can be expected ... ... ...
*Wednesday, March 25, 2015 at 12:25am*

**statistics**

A cereal company claims that 2 in every 15 boxes win a prize. What is the probability that you do not win a prize three times in a row?
*Tuesday, March 24, 2015 at 2:11am*

**Statistics**

The Economic Policy Institute periodically issues reports on wages of entry-level workers. The institute reported that entry-level wages for male college graduates were $21.68 per hour and for female college graduates were $18.80 per hour in 2011 (Economic Policy Institute ...
*Monday, March 23, 2015 at 2:29pm*

**Probability & Statistics**

To help consumers assess the risks they are taking, the Food and Drug Administration (FDA) publishes the amount of nicotine found in all commercial brands of cigarettes. A new cigarette has recently been marketed. The FDA tests on this cigarette yielded mean nicotine content ...
*Monday, March 23, 2015 at 12:08pm*

**Probability and Statistcis**

Students from a statistics class were asked to record their height in inches. The heights ( as recorded) were: 65, 72, 68, 64, 60, 55, 73, 71, 52, 63, 61, 74, 69, 67, 74, 50, 4, 75, 67, 62, 66, 80, 64, 65 Find five number summary.
*Sunday, March 22, 2015 at 9:29pm*

**Statistics**

I have a bunch of questions to work on with this specific scenario but I was hoping someone can just help me get started on the first one because I'm having trouble getting started and I'll do the rest on my own.Thanks for any help! In a southern state, it was revealed...
*Sunday, March 22, 2015 at 7:39pm*

**Intro statistics**

A bag contains 7 red, 6 orange, and 9 green jellybeans. What is the probability of reaching into the bag and randomly withdrawing 11 jelly beans such that the number of red ones is 7 the number of orange ones is 1 and the number of green ones is 3?
*Saturday, March 21, 2015 at 10:38pm*

**Economics**

China's slowdown Jan 20th 2015, 10:26 by S.R. | SHANGHAI MUCH of the analysis of China’s 2014 GDP data, which the government published today, has focused on the economy’s slowdown That is, on one level, understandable. Growth of 7.4% was China’s weakest in ...
*Saturday, March 21, 2015 at 3:07pm*

**statistics**

Average entry level salaries for college graduates with mechanical engineering degrees and electrical engineering degrees are believed to be approximately the same. A recruiting office thinks that the average mechanical engineering salary is actually lower than the average ...
*Friday, March 20, 2015 at 11:58pm*

**journalism check answers**

What is satire's underlying goal? to sell newspapers to shock people to get people to think c Many young people today get their news from which of the following unlikely sources? comedy shows such as "The Daily Show" their friends video games B Which of the ...
*Wednesday, March 18, 2015 at 10:41am*

**statistics**

There is a multiple choice exam with 24 questions, and five options each. If i guess every question, what is the probability that i will get exactly 15 correct.
*Tuesday, March 17, 2015 at 11:04pm*

**statistics **

Does a correlation ever prove causation? (For any subject/field?)
*Tuesday, March 17, 2015 at 10:21pm*

**statistics**

(10 pts) Using diaries for many weeks, a study on the lifestyles of visually impaired students was conducted. The students kept track of many lifestyle variables including how many hours of sleep obtained on a typical day. Researchers found that visually impaired students ...
*Tuesday, March 17, 2015 at 8:07pm*

**Statistics**

What do SEM (standard error of the mean) error bars tell you? How would you describe them in a figure caption for a graph? I know what regular error bars are, but I can't find any information on SEM error bars!
*Tuesday, March 17, 2015 at 7:06pm*

**Statistics**

A researcher predicts that watching a film on institutionalization will change students’ attitudes about chronically mentally ill patients. The researcher randomly selects 36 students, shows them the film, and gives them a questionnaire about their attitudes. The mean ...
*Monday, March 16, 2015 at 11:13pm*

**statistics**

In a certain lottery, five different numbers between 1 and 31 inclusive are drawn. These are the winning numbers. To win the lottery, a person must select the correct 5 numbers in the same exact order in which they were drawn. What is the probability of winning?
*Monday, March 16, 2015 at 11:36am*

**statistics**

According to a college survey, 22% of all students work full time. Find the mean and standard deviation for the number of students who work full time in samples of size 16.
*Monday, March 16, 2015 at 11:07am*

**statistics**

An unprepared student makes random guesses for the ten true-false questions on a quiz. Find the probability that there is at least one correct answer.
*Monday, March 16, 2015 at 11:06am*

**statistics**

The mayor of the town of Quahog, Rhode Island, Adam West, conducted a study to determine the mean household income of his constituents. The study surveyed 500 households and determined that the sample mean was $30,000. The population standard deviation is $4,800. If a ...
*Monday, March 16, 2015 at 10:41am*

**statistics**

A certain type of dvd player is sold at just two stores. 30% of sales are from store A and 70% of sales are from store B. 2.7% of the dvd players sold at store A are defective while 3.7% of the dvd players sold at store B are defective. If Kate receives one of these dvd ...
*Monday, March 16, 2015 at 9:06am*

**Business Statistics**

A firm claims that only 10% of it's accounts receivables are over 30 days past due. The bank that supplies working capital or interim loans to the firms is suspect of the figure and accordingly takes a random sample of 100 accounts of the firm. Find the probability that ...
*Monday, March 16, 2015 at 5:57am*

**Business Statistics**

A marketing class is engaged in a project to estimate the proportion of homes receiving both HBO and Showtime cable service. The class plans to use a confidence coefficient of 0.95 and a maximum error of the estimate equal to 0.10. Determine the sample size for the class to use.
*Monday, March 16, 2015 at 1:36am*

**Business Statistics**

A filling machine is designed to fill soda bottles with 16 ounces of soda. The distribution for the weight of the bottles is normal. Twenty bottles are selected and weighed. The sample mean is 15.3 ounces and sample standard deviation is 1.5 ounces. Develop a 90% confidence ...
*Monday, March 16, 2015 at 1:32am*

**Business Statistics**

There are 300 students enrolled in Business Statistic. Historically, exam scores are normally distributed with a standard deviation of 30.9. Your instructor randomly selected a sample of 30 examinations and finds a mean of 74.2. Determine a 90% confidence interval for the mean...
*Monday, March 16, 2015 at 1:26am*

**Statistics**

The average SAT score for the 300 students accepted at Tiny College this year is 1,050 with a standard deviation of 275. If a random sample of 40 students is selected from this class, what is the probability that the average SAT score will be greater than 1,000?
*Monday, March 16, 2015 at 1:21am*

**Statistics**

A firm claims that only 10% of its accounts receivables are over 30 days past due. The bank that supplies working capital or interim loans to the firm is suspect of the figure and accordingly takes a random of 100 accounts of the firm. Find probability that the sample ...
*Monday, March 16, 2015 at 1:16am*

**Statistics**

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes. what is the probability that a). it will take a technician less than 10 minutes to fix a computer problem? b) it will take a technician between 10 to 15 minutes to ...
*Sunday, March 15, 2015 at 11:42pm*

**Statistics**

the age of costumers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years. what is the probability that the next costumer who enters the store will be less than 42 years old?
*Sunday, March 15, 2015 at 10:11pm*

**Statistics**

in 2000, the averages change of tax preparation was $95. Assuming a normal distribution and a standard deviation of $10. What proportion of tax preparation fees were more than $95.
*Sunday, March 15, 2015 at 10:06pm*

**Statistics**

How many different ways can you put 3 distinguishable things in 10 boxes?
*Saturday, March 14, 2015 at 5:49pm*

**statistics**

A credit card company estimates that the average credit card balance of Americans is $3,210. A statistics student wants to know whether this is true for citizens of her home town. Which hypothesis test would be most appropriate for addressing this question? One sample z-test ...
*Saturday, March 14, 2015 at 3:36pm*

**statistics**

A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 395 babies were born, and 316 of them were girls. Use the sample data to construct a 99% confidence interval estimate of the percentage of girls born. Based on the result, ...
*Friday, March 13, 2015 at 9:49pm*

**Statistics**

80. Florida State University has 14 statistics classes scheduled for its Summer 2013 term. One class has space available for 30 students, eight classes have space for 60 students, one class has space for 70 students, and four classes have space for 100 students. a. What is the...
*Friday, March 13, 2015 at 8:24pm*

**Statistics - Can anybody help me?**

A Particular pain relieving medicine has a decay rate of 24% an hour. A patient was given a dose of the medicine 5 hours ago and there is currently 74mg of the medicine in the patients bloodstream. Q: What was the Origional dose of the medicine? ________ milligrams. Q How long...
*Friday, March 13, 2015 at 6:05pm*

**Statistics**

A Particular pain relieving medicine has a decay rate of 24% an hour. A patient was given a dose of the medicine 5 hours ago and there is currently 74mg of the medicine in the patients bloodstream. Q: What was the Origional dose of the medicine? ________ milligrams. Q How long...
*Friday, March 13, 2015 at 1:30pm*

**Statistics**

Good Afternoon, Hope everyone will have a nice weekend. I am sorry to bother you all, but I am failing statistic. Can someone give me an example of this and example of a regression hypothesis. Thank you
*Friday, March 13, 2015 at 12:42pm*

**statistics/probability**

An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 130 lb and 181 lb. The new population of pilots has normally distributed weights with a mean of 135 and a standard deviation of 25.1 lb. If a pilot is randomly ...
*Thursday, March 12, 2015 at 4:52pm*

**statistics**

The mean (μ) of the scale is 83 and the standard deviation (σ) is 10. Assuming that the scores are normally distributed, what is the PROBABILITY that a score falls below 72?
*Thursday, March 12, 2015 at 4:27pm*

**statistics**

The average age of doctors in certain hospital is 43 years old. Suppose distribution of ages is normal and the standard deviation is 8.0 years. If 25 doctors is chosen at random for a committee, find the probability the average age for those doctors is less than 43.8 years. ...
*Wednesday, March 11, 2015 at 8:39pm*

**statistics**

A casting director wishes to find one male and one female to cast is his play. If he plans to audition 5 males and 7 females, in how many different ways can this be done? DO NOT put a comma in your response.
*Wednesday, March 11, 2015 at 8:18pm*

**Statistics**

Shopping Outlet A shopping outlet estimates the probability distribution of the number of stores shoppers actually enter as shown in the table below. x 0 1 2 3 4 p(x) 0.05 0.35 0.25 0.20 0.15 What is the probability that shoppers are just window shopping and not entering any ...
*Wednesday, March 11, 2015 at 1:25am*

**Statistics**

In the following problem, check that it is appropriate to use the normal approximation to the binomial. Then use the normal distribution to estimate the requested probabilities. More than a decade ago, high levels of lead in the blood put 87% of children at risk. A concerted ...
*Tuesday, March 10, 2015 at 10:43pm*

**Elementary Statistics **

"Scores on the Wechsler IQ test approximate a normal curve with a mean of 100 and a standard deviation of 15. b. What percentage of IQ scores are below 74?" I've been working at this for a while now, but when I solve for the z-score, I keep getting a negative ...
*Tuesday, March 10, 2015 at 10:33pm*

**statistics **

Z-test. How to find critical value for one tail test?
*Tuesday, March 10, 2015 at 8:07pm*