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March 27, 2015

March 27, 2015

**Recent Homework Questions About Statistics**

Post a New Question | Current Questions

**statistics**

A researcher believe that college students spend a different amount of time talking on the phone than they do instant messaging. She takes a random sample of 12 college students and records the number of hours per week each student spends on each activity and plans to test at ...
*Saturday, April 26, 2014 at 11:34am*

**ap statistics**

A fire insurance company felt that the mean distance from a home to the nearest fire department in a suburb of Chicago was at least 4.7 miles. It set its fire insurance rates accordingly. Members of the community set out to show that the mean distance was less than 4.7 miles. ...
*Friday, April 25, 2014 at 9:35pm*

**ap statistics**

The manager at Air Cargo feels that the weights of packages shipped recently are less than in the past. Records show that in the past packages have had a mean weight of 36.7 lb. and a variance of 201.64 lb2. A random sample of last months shipping yielded a mean weight of 32.1...
*Friday, April 25, 2014 at 9:33pm*

**statistics**

Which of the following statements is correct? A. An extremely small p-value indicates that the actual data differs markedly from that expected if the null hypothesis were true. B. A large p-value indicates that the data is consistent with the alternative hypothesis. C. The p-...
*Friday, April 25, 2014 at 10:29am*

**ap statistics**

What is the mean of the sample means? What is the standard deviation of the sample means?
*Friday, April 25, 2014 at 9:43am*

**Statistics **

For the following set of scores: X Y 6 4 3 1 5 0 6 7 4 2 6 4 a) Compute the Pearson correlation. b) Add 2 points to each X value and compute the correlation for the modified scores. How does adding a constant to every score affect the value of the correlation? c)Multiply each ...
*Thursday, April 24, 2014 at 10:54pm*

**statistics**

In which of the following situations would it not be appropriate to use a paired t-test to analyze the data? A. A marriage therapist believes that many couples have different perspectives regarding the state of their marriages, prior to the start of couples therapy. In order ...
*Thursday, April 24, 2014 at 9:14pm*

**Statistics**

From the following list of number of discharges each day in September, compute the mean, median, mode, and range. Round the mean and median to one decimal point. Day # of discharges 1 27 2 22 3 35 4 63 5 42 6 55 7 62 8 65 9 32 10 35 11 36 12 75 13 65 14 84 15 37 16 38 17 62 18...
*Thursday, April 24, 2014 at 5:25pm*

**ap statistics**

Which of the following is not correct? A. The rejection region is controlled by the alpha level and the alternate hypothesis. B. The p-value measures the probability that the null hypothesis is true. C. The probability of a Type I error is controlled by the selection of the ...
*Thursday, April 24, 2014 at 3:55pm*

**ap statistics**

In hypothesis testing, β is the probability of committing an error of Type II. The power of the test, 1 - β, is then: A. the probability of failing to reject H0. B. the probability of rejecting H0 when HA is true C. the probability of failing to reject H0 when H0 is ...
*Thursday, April 24, 2014 at 3:51pm*

**ap statistics**

An unnoticed mechanical failure has caused one-fourth of a machine shop’s production of 10000 pistol firing pins to be defective. A random sample of 25 firing pins was drawn from the population. a.) Explain why this random variable has a binomial distribution? (2 points) ...
*Thursday, April 24, 2014 at 3:20pm*

**ap statistics**

An unnoticed mechanical failure has caused one-fourth of a machine shop’s production of 10000 pistol firing pins to be defective. A random sample of 25 firing pins was drawn from the population. a.) Explain why this random variable has a binomial distribution? (2 points) ...
*Thursday, April 24, 2014 at 3:08pm*

**ap statistics**

What is the mean of the sample means? What is the standard deviation of the sample means?
*Thursday, April 24, 2014 at 3:08pm*

**ap statistics**

In a survey, 600 mothers and fathers were asked about the importance of sports for boys and girls. Of the parents interviewed, 70% said the genders are equal and should have equal opportunities to participate in sports. B. Using the normal approximation without the continuity ...
*Thursday, April 24, 2014 at 2:54pm*

**ap statistics**

An unnoticed mechanical failure has caused one-fourth of a machine shop’s production of 10000 pistol firing pins to be defective. A random sample of 25 firing pins was drawn from the population. a.) Explain why this random variable has a binomial distribution? (2 points) ...
*Thursday, April 24, 2014 at 2:34pm*

**Statistics**

Prof. C is studying a population of the elementary school pupils in a school district with data on all its children. Another prof. suggests he calculate a confidence interval to estimate the mean age of the children. Prof C responds that it is not necessary. Explain why Prof. ...
*Wednesday, April 23, 2014 at 11:51pm*

**statistics (7)**

The average cost per night of a hotel room in New York City is $273 (SmartMoney, March 2009). Assume this estimate is based on a sample of 45 hotels and that the sample standard deviation is $65. a. With 95% confidence, what is the margin of error (to 2 decimals)? b. What is ...
*Wednesday, April 23, 2014 at 9:11pm*

**statistics (6)**

The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airports. The maximum possible rating is 10. Suppose a simple random sample of 50 business travelers is selected and each traveler is asked to provide a ...
*Wednesday, April 23, 2014 at 8:44pm*

**statistics (4)**

For a t distribution with 16 degrees of freedom, find the area, or probability, in each region. a. To the right of 2.120. (Use 3 decimals.)
*Wednesday, April 23, 2014 at 8:44pm*

**statistics (10)**

Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $30,000 and $45,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. What is the planning value ...
*Wednesday, April 23, 2014 at 8:43pm*

**Statistics and probability**

a sample of 500 drivers was asked whether or not they speed while driving. The following table gives a two-way classification: speed Never Speed totals male 222 78 300 female 128 72 200 totals 350 150 500 We wish to test whether gender and speeding are related at the 1% ...
*Wednesday, April 23, 2014 at 4:09pm*

**statistics**

Data were collected on 100 students regarding their class and major. The data are summarized in the following contingency table. What is the probability of randomly selecting a sophomore or an undeclared student?
*Wednesday, April 23, 2014 at 11:23am*

**statistics (10)**

Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $30,000 and $45,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. What is the planning value ...
*Tuesday, April 22, 2014 at 11:15pm*

**statistics (7)**

The average cost per night of a hotel room in New York City is $273 (SmartMoney, March 2009). Assume this estimate is based on a sample of 45 hotels and that the sample standard deviation is $65. a. With 95% confidence, what is the margin of error (to 2 decimals)? b. What is ...
*Tuesday, April 22, 2014 at 11:08pm*

**statistics (4)**

For a t distribution with 16 degrees of freedom, find the area, or probability, in each region. a. To the right of 2.120. (Use 3 decimals.)
*Tuesday, April 22, 2014 at 11:05pm*

**statistics (6)**

The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airports. The maximum possible rating is 10. Suppose a simple random sample of 50 business travelers is selected and each traveler is asked to provide a ...
*Tuesday, April 22, 2014 at 11:04pm*

**Statistics PLEASE HELP ME!**

The Wall Street Journal reported that automobile crashes cost the United States $162 billion annually (The Wall Street Journal, March 5, 2008). The average cost per person for crashes in the Tampa, Florida, area was reported to be $1599. Suppose this average cost was based on ...
*Tuesday, April 22, 2014 at 10:38pm*

**Statistics**

The ABC Self-Concept Inventory has a split- half reliability coefficient of 0.90 and the XYZ Self-Concept Inventory has a Spearman- Brown reliability coefficient of 0.90. And if all factors are equal, which instrument would be chose to use?
*Tuesday, April 22, 2014 at 3:13pm*

**statistics**

If M=1000; SD=200. What score do 20% of the test-takers score?
*Tuesday, April 22, 2014 at 12:23pm*

**statistics**

We guess, based on historical data, that 30% of graduating high-school seniors in a large city will have completed a first-year calculus course. What's the minimum sample size needed to construct a 95% confidence interval for a proportion with a margin of error of 2.5%?
*Tuesday, April 22, 2014 at 11:56am*

**statistics**

The process that produces Sonora Bars (a type of candy) is intended to produce bars with a mean weight of 55 gm. The process standard deviation is known to be 0.77 gm. A random sample of 49 candy bars yields a mean weight of 55.82 gm. Find the test statistic to see whether the...
*Tuesday, April 22, 2014 at 10:46am*

**statistics**

If an instrument requires some professional judgments in scoring, then the manual should also include information on a. Interrater RELIABILITY b. Corrections of the reliability coefficients using the Spearman-Brown formula c, Both KR 20s and KR 21s d. Test retest reliability ...
*Monday, April 21, 2014 at 9:12pm*

**statistics**

Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $30,000 and $45,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. What is the planning value ...
*Monday, April 21, 2014 at 7:39pm*

**statistics**

How large a sample should be selected to provide a 95% confidence interval with a margin of error of 10 (to the nearest whole number)? Assume that the population standard deviation is 40.
*Monday, April 21, 2014 at 7:38pm*

**statistics**

The average cost per night of a hotel room in New York City is $273 (SmartMoney, March 2009). Assume this estimate is based on a sample of 45 hotels and that the sample standard deviation is $65. a. With 95% confidence, what is the margin of error (to 2 decimals)? b. What is ...
*Monday, April 21, 2014 at 7:38pm*

**statistics**

The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airports. The maximum possible rating is 10. Suppose a simple random sample of 50 business travelers is selected and each traveler is asked to provide a ...
*Monday, April 21, 2014 at 7:38pm*

**statistics**

For a t distribution with 16 degrees of freedom, find the area, or probability, in each region. a. To the right of 2.120. (Use 3 decimals.) b. To the left of 1.337. (Use 2 decimals.) c. To the left of -1.746. (Use 2 decimals.) d. To the right of 2.583. (Use 2 decimals.) e. ...
*Monday, April 21, 2014 at 7:37pm*

**statistics**

The Wall Street Journal reported that automobile crashes cost the United States $162 billion annually (The Wall Street Journal, March 5, 2008). The average cost per person for crashes in the Tampa, Florida, area was reported to be $1599. Suppose this average cost was based on ...
*Monday, April 21, 2014 at 7:36pm*

**statistics**

A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is 5. a. What is the standard error of the mean (to 2 decimals)? b. At 95% confidence, what is the margin of error (to 2 decimals)?
*Monday, April 21, 2014 at 7:35pm*

**statistics**

Using the 95% level of confidence, what is the confidence interval for the proportion of households represented at a town meeting
*Monday, April 21, 2014 at 4:12pm*

**Statistics**

On an exam on probability concepts, Sue had an answer of 13/8 for one problem. Explain how she knew that this result was incorrect.
*Sunday, April 20, 2014 at 11:27pm*

**statistics**

A sociologist is interested in the relation between x = numberof job changes and y = annual salary (in thousands of dollars) forpeople living in the Nashville area. A random sample of 10people employed in Nashville provided the followinginformation: x (number of job changes) 4...
*Sunday, April 20, 2014 at 5:43pm*

**Statistics**

Recently, a university surveyed recent graduates of the English Department for their starting salaries. Four hundred graduates returned the survey. The average salary was $25,577. The population standard deviation is $2,566. What is the 95% confidence interval for the mean ...
*Sunday, April 20, 2014 at 5:41pm*

**Statistics**

A survey of an urban university (population of 25,450) showed that 878 of 1,119 students sampled supported a fee increase to fund improvements to the student recreation center. Using the 95% level of confidence, what is the confidence interval for the proportion of students ...
*Sunday, April 20, 2014 at 3:45pm*

**Statistics**

Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The results showed that the average tread life was 52,515 miles with a standard deviation of 3,550 miles. What is the best estimate of the average tread life in miles for the ...
*Sunday, April 20, 2014 at 3:27pm*

**statistics**

Fill in the blanks with the appropriate raw scores, z-scores, T-scores, and percentile ranks. NOTE: the Mean = 50, SD = 5. ________________________________________ Raw z T %ile ________________________________________ 35 1.2 35 16
*Sunday, April 20, 2014 at 10:40am*

**statistics**

P(-1.86<z<0)=
*Sunday, April 20, 2014 at 10:38am*

**statistics**

The Acme Candy Company claims that 60% of the jawbreakers it produces weigh more than .4ounces. Suppose that 800 jawbreakers are selected at random from the production lines. Would it be unusual for this sample of 800 to contain 494 jawbreakers that weigh more than .4 ounces?
*Sunday, April 20, 2014 at 8:32am*

**statistics**

data shows number of absent student of statistic ciass. 3,5,7,4,6,0,1,4,3,2,8,5,4,7,1,5,2,6,7,8,3,9,1,0,5,6, form a frequency distribution by taking one class interval.
*Sunday, April 20, 2014 at 5:39am*

**statistics**

discuss the contribution of computer in the development of science and technology
*Sunday, April 20, 2014 at 5:33am*

**statistics**

3coins are tossed calculate the followin probabilities p(3heads) p(2heads and 1 tail) p(3 tails)
*Sunday, April 20, 2014 at 5:20am*

**statistics**

The average age for licensed drivers in a county is µ= 42.6, σ= 12 and the distribution is approximately normal. A county police officer was interested in whether the average age of those receiving parking tickets in the county differed from that of the average age ...
*Saturday, April 19, 2014 at 6:59pm*

**statistics**

Scores on a national exam assume a normal distribution with a population mean of 50 and population standard deviation of 10 points. A sample of 36 exam scores was selected from UCA with a mean score of 58 points. Using a significance level of 0.01, determine whether scores on ...
*Friday, April 18, 2014 at 8:49pm*

**statistics**

The mean score for all individuals who took the Law School Admission Test (LSAT) in 2010 was 155 and the standard deviation was 7. 9. What is the z score for a person, who received an LSAT score of 167? a. +1.71 b. +1.64 c. +1.74 d. -1.71 10.What is the raw score for a person ...
*Friday, April 18, 2014 at 8:42pm*

**Statistics**

A random sample of 47 students studied for an average of 7.1 hours last week. If the population standard deviation is 1.2 hours, what is the 90% confidence interval for the population mean?
*Friday, April 18, 2014 at 11:19am*

**Statistics **

A sample of 50 homes in a subdivision revealed that 24 were ranch style. a) Construct a 98 percent confidence interval for the true proportion of ranch-style homes b) Check the normaility assumption.
*Friday, April 18, 2014 at 9:57am*

**statistics**

in throwing two dice find the probability ofcoming even number on both probability of coming odd number on dice probability of different number on both dice
*Friday, April 18, 2014 at 9:24am*

**statistics**

a box contain five silp of paper marked 1,2,3,4and5 tow silp are selected without replacement,list the possible vaule for each of following random variable the sum of two number on two silp the difference between the first and second number
*Friday, April 18, 2014 at 9:17am*

**Statistics**

Hi, Are market returns (with numbers such as -3.45, 4, 2.456 representing the "returns") ordinal or nominal data? Thanks!
*Friday, April 18, 2014 at 1:40am*

**Statistics Emergency please**

People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a)What is the probability ...
*Thursday, April 17, 2014 at 1:17pm*

**Statistics Emergency please**

People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a.Show the sampling ...
*Thursday, April 17, 2014 at 12:34pm*

**Language Arts**

Read the following sentence from the editorial: "We learn that all of our moments can be filled with joy if we only open our hearts to our pets." How is faulty reasoning shown in this sentence? A. The author exaggerates the effect of owning a pet. B. The author makes...
*Thursday, April 17, 2014 at 11:09am*

**statistics**

According to an Internet posting, 80% of adults enjoy drinking beer. If a group of 3 adults is selected at random, find the probability that all of them enjoy drinking beer is:
*Thursday, April 17, 2014 at 12:27am*

**statistics**

A standardized third grade reading test, called the We Can Read Test, has a mean of 50 with a standard deviation of 10. A developmental psychologist conducts a study, where he assesses the reading ability of a random sample of 75 third graders using the We Can Read Test, and ...
*Wednesday, April 16, 2014 at 7:48pm*

**Statistics**

People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a.Show the sampling ...
*Wednesday, April 16, 2014 at 5:05pm*

**Statistics**

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...
*Wednesday, April 16, 2014 at 5:04pm*

**Statistics**

A survey asked 2000 people whether or not they frequently exceed the speed limit. The collected data is summarized in the following contingency table. The goal is to determine if there is a difference in the population proportion that say “yes” when comparing those ...
*Wednesday, April 16, 2014 at 2:24pm*

**Statistics**

An ESP experiment is done in which a participant guesses which of 8 cards the researcher has randomly picked, where each card is equally likely to be selected. This is repeated for 200 trials. The null hypothesis is that the subject is guessing, while the alternative is that ...
*Wednesday, April 16, 2014 at 12:20pm*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*Wednesday, April 16, 2014 at 11:04am*

**statistics**

The Good Mental Health Insurance Company has determined the number of new clients a psychologist gets per month and their respective probabilities, as shown in the table below: Number of New Clients Probability 0 0.05 1 0.10 2 0.15 3 0.35 4 0.20 5 0.10 6 0.05 The probability ...
*Wednesday, April 16, 2014 at 8:49am*

**statistics**

A standardized third grade reading test, called the We Can Read Test, has a mean of 50 with a standard deviation of 10. A developmental psychologist conducts a study, where he assesses the reading ability of a random sample of 75 third graders using the We Can Read Test, and ...
*Wednesday, April 16, 2014 at 8:37am*

**statistics**

People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a.Show the sampling ...
*Tuesday, April 15, 2014 at 10:06pm*

**statistics**

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...
*Tuesday, April 15, 2014 at 10:02pm*

**statistics**

Suppose a random sample of size 50 is selected from a population with σ = 10. Find the value of the standard error of the mean in each of the following cases (use the finite population correction factor if appropriate). a. The population size is infinite (to 2 decimals). ...
*Tuesday, April 15, 2014 at 10:00pm*

**statistics**

The American Association of Individual Investors (AAII) polls its subscribers on a weekly basis to determine the number who are bullish, bearish, or neutral on the short-term prospects for the stock market. Their findings for the week ending March 2, 2006, are consistent with ...
*Tuesday, April 15, 2014 at 9:59pm*

**statistics**

A standardized third grade reading test, called the We Can Read Test, has a mean of 50 with a standard deviation of 10. A developmental psychologist conducts a study, where he assesses the reading ability of a random sample of 75 third graders using the We Can Read Test, and ...
*Tuesday, April 15, 2014 at 7:17pm*

**statistics**

The mean score for all individuals who took the Law School Admission Test (LSAT) in 2010 was 155 and the standard deviation was 7. What is the z score for a person, who received an LSAT score of 167? a. +1.71 b. +1.64 c. +1.74 d. -1.71 What is the raw score for a person with a...
*Tuesday, April 15, 2014 at 6:48pm*

**statistics**

The Good Mental Health Insurance Company has determined the number of new clients a psychologist gets per month and their respective probabilities, as shown in the table below: Number of New Clients Probability 0 0.05 1 0.10 2 0.15 3 0.35 4 0.20 5 0.10 6 0.05 The probability ...
*Tuesday, April 15, 2014 at 4:39pm*

**statistics**

A standardized third grade reading test, called the We Can Read Test, has a mean of 50 with a standard deviation of 10. A developmental psychologist conducts a study, where he assesses the reading ability of a random sample of 75 third graders using the We Can Read Test, and ...
*Tuesday, April 15, 2014 at 4:21pm*

**Statistics**

Find the indicated probability using the standard normal distribution: P(z<-1.45)
*Tuesday, April 15, 2014 at 1:29pm*

**statistic**

Listed below are the ages of actresses and actors at the times that they won Oscars for the categories of Best Actress and Best Actor. The ages are listed in chronological order by row, so that corresponding locations in the two tables are from the same year. (Notes: In 1968 ...
*Tuesday, April 15, 2014 at 1:10pm*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*Tuesday, April 15, 2014 at 12:59pm*

**statistics**

A manufacturer ships toasters in cartons of 50. In each carton, they estimate a 2% chance that one of the toasters will need to be sent back for minor repairs. In a batch of 25,000 toasters, what are the chances that fewer than 475 need to be returned? The probability that ...
*Tuesday, April 15, 2014 at 12:02pm*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*Tuesday, April 15, 2014 at 10:24am*

**statistics**

Which of the following percentiles corresponds to the area beneath the standard normal curve from a z score of-3.00 to + 3.00? a. 98% b. 100% c. 95% d. 99.7%
*Tuesday, April 15, 2014 at 8:33am*

**statistics**

Jorge finds that his standardized z score on an IQ is 2.0. What percentage of people did he score higher than? a. 98 b. 96 c. 68 d. 34
*Tuesday, April 15, 2014 at 8:31am*

**statistics**

Professor Smith gave a final exam in her history class. The scores on the final exam are normally distributed with a mean of 75 and a standard deviation of 6. If Professor Smith wishes to give A’s to the top 4%, what would be the cutoff score be for A’s? a. 90.0 b. ...
*Monday, April 14, 2014 at 11:25pm*

**statistics**

It is known that the population mean for the Full Scale IQ of the WAIS is 100 with a standard deviation of 15. A researcher assesses a sample of 200 adults and find that they have a mean Full Scale IQ of 102. The point estimate of the mean for this group is ___________ and the...
*Monday, April 14, 2014 at 11:18pm*

**statistics**

Ashley and Sanjay are donating blood at a local hospital. As a standard practice, the blood is screened for anemia (low levels of red blood cells), and the results are given to each donor as a z score, ranging from negative scores (low amounts of red blood cells, anemic) to ...
*Monday, April 14, 2014 at 10:49pm*

**statistics**

Leslie took two midterm exams and earned the following scores: 82 on the chemistry exam (class distribution: μ = 75, σ = 6.25) and 63 on the physics exam (class distribution: μ = 59, σ = 3.57). Rounding to two decimal points, on which exam should Leslie get...
*Monday, April 14, 2014 at 10:27pm*

**statistics**

People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a. Show the sampling ...
*Monday, April 14, 2014 at 5:17pm*

**statistics**

Assume that the population proportion is .55. Compute the standard error of the proportion, ( ), for sample sizes of 100, 200, 500, and 1000 (to 4 decimals). a. 100? b. 200? c. 500? d. 1000?
*Monday, April 14, 2014 at 5:16pm*

**statistics**

The College Board reported the following mean scores for the three parts of the Scholastic Aptitude Test (SAT) (The World Almanac, 2009): Assume that the population standard deviation on each part of the test is = 100. a. What is the probability a sample of 90 test takers will...
*Monday, April 14, 2014 at 5:15pm*

**statistics**

Suppose a random sample of size 50 is selected from a population with σ = 10. Find the value of the standard error of the mean in each of the following cases (use the finite population correction factor if appropriate). a. The population size is infinite (to 2 decimals). ...
*Monday, April 14, 2014 at 5:14pm*

**statistics**

Many drugs used to treat cancer are expensive. BusinessWeek reported on the cost per treatment of Herceptin, a drug used to treat breast cancer (BusinessWeek, January 30, 2006). Typical treatment costs (in dollars) for Herceptin are provided by a simple random sample of 10 ...
*Monday, April 14, 2014 at 5:10pm*

**statistics**

What is wrong with the statement: It is believed that the proportion of Middle School teachers who leave the profession within 5 years is different from the proportion of High School teachers who leave the profession within 5 years. Test with a level of significance of 0.05. ...
*Monday, April 14, 2014 at 1:05pm*

**statistics**

the subway train has 18 doors and starts with 15 passenger. if each passenger is equally likely to get off at any station and the passengers leave the train independently, find the probability that 2 or more passengers leave the train through the same door
*Sunday, April 13, 2014 at 10:28pm*

**statistics**

In testing a new drug, researchers found that 10% of all patients using it will have a mild side effect. A random sample of 12 patients using the drug is selected. If you wanted to find the probability that exactly three will have this mild side effect, what would be the ...
*Saturday, April 12, 2014 at 11:59pm*

**Statistics **

Information from the American Institute of Insurance indicates the mean amount of life insurance per household in the United States is $120,000. This distribution follows the normal distribution with a standard deviation of $38,000. (A) If we select a random sample of 58 ...
*Friday, April 11, 2014 at 11:35pm*

**Statistics **

A cola-dispensing machine is set to dispense a mean of 2.024 liters into a container labeled 2 liters. Actual quantities dispensed vary and the amounts are normally distributed with a standard deviation of 0.040 liters. What is the probability a container will have less than 2...
*Friday, April 11, 2014 at 7:11pm*

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