Sunday

February 7, 2016
**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 by Kevin*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Hani*

**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 by k*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Natalie*

**statistics**

If M=1000; SD=200. What score do 20% of the test-takers score?
*Tuesday, April 22, 2014 by Yolanda*

**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 by nicole*

**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 by Anonymous*

**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 by Natalie*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Jay*

**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 by Traci*

**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 by John*

**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 by Ray*

**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 by Ray*

**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 by Ray*

**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 by Judi*

**statistics**

P(-1.86<z<0)=
*Sunday, April 20, 2014 by teri*

**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 by Anonymous*

**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 by shumaila.imtiaz*

**statistics**

discuss the contribution of computer in the development of science and technology
*Sunday, April 20, 2014 by shumaila.imtiaz*

**statistics**

3coins are tossed calculate the followin probabilities p(3heads) p(2heads and 1 tail) p(3 tails)
*Sunday, April 20, 2014 by shumaila.imtiaz*

**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 by Mark*

**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 by Anonymous*

**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 by Marty*

**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 by Monica*

**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 by Dayna *

**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 by shumaila.imtiaz*

**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 by shumaila.imtiaz*

**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 by Candice*

**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 by Vanessa*

**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 by Vanessa*

**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 by Destany *

**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 by Bertha*

**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 by Carrie*

**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 by Vanessa*

**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 by Vanessa*

**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 by Mea*

**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 by Mea*

**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 by Stacey*

**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 by Lee*

**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 by Lee*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Lee*

**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 by Stacey*

**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 by Lee*

**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 by Lee*

**Statistics**

Find the indicated probability using the standard normal distribution: P(z<-1.45)
*Tuesday, April 15, 2014 by Me*

**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 by Bell*

**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 by Katie*

**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 by Abby*

**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 by Katie*

**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 by Katie*

**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 by Katie*

**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 by Sally*

**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 by Sally*

**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 by Sally*

**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 by Sally*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Vanessa*

**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 by Terri*

**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 by linn*

**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 by Pista*

**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 by Student5*

**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 by Student5*

**Statistics**

An accelerated life test on a large number of type-D alkaline batteries revealed that the mean life for a particular use before they failed is 19.0 hours. The distribution of the lives approximated a normal distribution. The standard deviation of the distribution was 1.2 hours...
*Friday, April 11, 2014 by Ryan*

**Elementary Statistics**

There are 100 questions from an SAT test, and they are all multiple choice with possible answers of a,b,c,d,e. For each question, only one answer is correct, find the standard deviation for the numbers of correct answers for those who make random guesses for all 100 questions.
*Friday, April 11, 2014 by Confused*

**Statistics **

Daily output of Marathon's Grayville, LA, Refinery is normally Distributed with a mean of 232,000 barrels of crude oil per day with a standard deviation of 7,000 barrels. a. what is the probability of producing at least 232,000 barrels? b. between 232,000 and 239,000 ...
*Friday, April 11, 2014 by Lindsay *

**Statistics **

The Weight of a small Starbucks coffee is normally distributed random variable with a mean of 360 grams and a standard deviation of 9 grams. Find the weight that corresponds to each event. a. highest 10% b. highest 50% c. highest 5% D. highest 80% e. lowest 10% f. middle 50% g...
*Friday, April 11, 2014 by Kelly*

**Statistics **

The Amount of filling a half-liter (500ml)soft drink bottle is normally distributed. The process has a standard deviation of 5ml. The mean is adjustable. A. Where should the mean be set to ensure a 95% probability that a half-liter bottle will not be under filled? B. A 99% ...
*Friday, April 11, 2014 by KT*

**statistics**

Times for a surgical procedure are normally distributed. There are two methods. Method A has a mean of 28 Minutes and a standard deviation of 4 minutes, while B has a mean of 32 minutes and a standard deviation of 2 minutes. a)which procedure is preferred if the procedure must...
*Friday, April 11, 2014 by Rontheman*

**statistics**

A large number of applicants for admission to graduate study in business are given an aptitude test with a resulting mean score of 460 with a standard deviation of 80. The top 2.5 percent of the applicants would have a score of at what? A. 606 B. 617 C. 600 D. 646
*Friday, April 11, 2014 by Jill*

**statistics; emergency please help me**

Assume a binomial probability distribution has p = .60 and n = 200. a. What is the probability of 100 to 110 successes (to 4 decimals)? b. What is the probability of 130 or more successes (to 4 decimals)?
*Thursday, April 10, 2014 by Vanessa*

**statistics; emergency please help me**

Given that z is a standard normal random variable, compute the following probabilities (to 4 decimals). a. P(z -1.5) b. P(z -2.5)
*Thursday, April 10, 2014 by Vanessa*

**Statistics**

If a company’s total fixed costs increased by $20,000 and its contribution margin decreased by $12,000, net income would be?
*Thursday, April 10, 2014 by Betty*

**statistics**

Collina’s Italian Café in Houston, Texas, advertises that carryout orders take about 25 minutes (Collina’s website, February 27, 2008). Assume that the time required for a carryout order to be ready for customer pickup has an exponential distribution with a ...
*Wednesday, April 9, 2014 by Vanessa*

**statistics**

There are 652 males, 396 say they have been to dentist in past year. Give a confidence interval for 90% of the population proportion.
*Wednesday, April 9, 2014 by Anonymous*

**Statistics**

When is it appropriate to draw a causal connection between two measurement variables? In other words, what conditions must be met in the study and in the analysis to show a causal relationship? My answer : 1.There needs to be a reasonable explanation of cause and effect. 2.The...
*Wednesday, April 9, 2014 by Mea*

**statistics**

A survey was taken in various Statistics classes and the following regression equation was obtained regarding the height and weight of students in the Statistics classes. Regression equation Height = 56.8 + 0.0712 Weight Given the regression equation above, what is the correct...
*Wednesday, April 9, 2014 by Mea*

**Statistics**

Suppose that 50% of people frequently exceed the speed limit. A random sample of 2000 people is surveyed and 55% indicate that they frequently speed. What is the value of the population percent given to you in the problem?
*Wednesday, April 9, 2014 by Mea*