Thursday

January 19, 2017
Number of results: 13,517

**math**

Let x1,x2,x3 be random sample of normal(6,4)(x+1)/2,-1<x<1,find P(max{x1,x2,x3}>8)

*December 28, 2014 by assma*

**math**

Let x1,x2,x3 be random sample of f(x)=2x,0<x<1,zero elsewhere find P(x1/x2<0.5)

*December 28, 2014 by assma*

**Statistics and Probability**

Suppose you took 1000 random samples of size 200 from the Poisson distribution with u = 5 and computed a 90% confidence interval for each sample. Approximate the probability that at least 920 of these intervals would contain the mean value u = 5. Be sure to define any random ...

*March 26, 2011 by Adam HELP PLEASEEE*

**Statistics and Probability**

Suppose you took 1000 random samples of size 200 from the Poisson distribution with u = 5 and computed a 90% confidence interval for each sample. Approximate the probability that at least 920 of these intervals would contain the mean value u = 5. Be sure to define any random ...

*March 27, 2011 by Adam *

**Statistics**

4 calculators were selected at random from a sample of 44 calculators that were defective and 22 that were in good condition. Find the probability that all 4 calculators are defective. Ok, I'll just start this one. There are 66 choose 4 samples. yes/no? What is the P of 0,1,2,...

*July 14, 2006 by I love math & science !*

**Statistics**

A random sample of 51 of the largest companies in the united states gave the following P/e ratios 11 35 19 13 15 21 40 18 60 72 9 20 29 53 16 26 21 14 21 27 10 12 47 14 33 14 18 17 20 19 13 25 23 27 5 16 8 49 44 20 27 8 19 12 31 67 51 26 19 18 32 Use a calculator with mean and...

*June 11, 2011 by Anonymous*

**Statistics**

A random sample of 51 of the largest companies in the united states gave the following P/e ratios 11 35 19 13 15 21 40 18 60 72 9 20 29 53 16 26 21 14 21 27 10 12 47 14 33 14 18 17 20 19 13 25 23 27 5 16 8 49 44 20 27 8 19 12 31 67 51 26 19 18 32 Use a calculator with mean and...

*June 11, 2011 by Anonymous*

**statistics**

A random sample of 51 of the largest companies in the united states gave the following P/e ratios 11 35 19 13 15 21 40 18 60 72 9 20 29 53 16 26 21 14 21 27 10 12 47 14 33 14 18 17 20 19 13 25 23 27 5 16 8 49 44 20 27 8 19 12 31 67 51 26 19 18 32 Use a calculator with mean and...

*June 11, 2011 by Anonymous*

**statistics**

A random sample of 51 of the largest companies in the united states gave the following P/e ratios 11 35 19 13 15 21 40 18 60 72 9 20 29 53 16 26 21 14 21 27 10 12 47 14 33 14 18 17 20 19 13 25 23 27 5 16 8 49 44 20 27 8 19 12 31 67 51 26 19 18 32 Use a calculator with mean and...

*June 11, 2011 by Anonymous*

**statistics**

An agricultural economist is interested in determining the average diameter of peaches produced by a particular tree. A random sample of 50 peaches is taken and the sample mean calculated. Suppose that the average diameter of peaches on this tree is known from previous years' ...

*March 26, 2012 by Pat*

**Stat college**

It is estimated that 17% of americans have blue eyes. A random sample of 9 americans is selected. Find the probability that the sample includes exactly 2 people with blue eyes. Find the probability that the sample includes at most 2 people with blue eyes. Find the mean number ...

*May 6, 2014 by redd*

**Math**

A toothpaste company did a survey at the mall. They found that 42.5% of those surveyed brushed their teeth twice a day. Which random numbers would you generate on a computer spreadsheet to simulate the survey? a. random integers from 425 to 1000 b. random integers from 1 to ...

*December 12, 2013 by Brandi*

**Statistics**

I have a question that involves explaining what is wrong in each of the following situations: (a) A random sample of size 20 is taken from a population that is assumed to have a standard deviation of 12. The standard deviation of the sample mean is 12/20. (b) A researcher ...

*March 29, 2009 by Lynn*

**Statistics**

The International Olympic Committee states that the female participation in the 2000 Summer Olympic Games was 42%, even with new sports such as weight lifting, hammer throw, and modern pentathlon being added to the Games. Broadcasting and clothing companies want to change ...

*October 29, 2007 by LT*

**Prob and Stat**

A tire manufacturer guarantess that its tires will last for at least 60,000 miles. If the tire fails earlier, the manufacturer offers a prorated replacement. Too many such replacements are bad for business, so the manufacturer tests tires at random to see whether corrective ...

*May 17, 2011 by Angela*

**Statics**

You suspect that, on the average, professional baseball players are older than professional football players. A random sample of 30 professional baseball players has a mean age of 28.8 years (assume ó = 4). A random sample of 40 professional football players has a mean age of...

*December 2, 2012 by Heather*

**Statistics**

Consider the hypothesis test given by Ho:u=530, H1:u does not equal 530. In a random sample of 85 subjects, the sample mean is found to be 522.3. Also, the population standard deviation is 29. Determine the P-value for this test. Is there sufficient evidence to justify the ...

*March 8, 2013 by Sandy*

**STAT**

it is estimated that 17% of americans have blue eyes. A random sample of 9 americans is selected. Find the probability that the sample includes exactly 2 people with blue eyes. Find the probability that the sample includes at most 2 people with blue eyes. Find the mean number ...

*May 6, 2014 by Anonymous*

**statistics**

Starting with a population that is normally distributed with a mean of 100 and a standard deviation of 12, answer the following questions (if possible). a. What is the probability of randomly drawing a single score between 100 and 106, p(100 < X < 106)? b. What is the ...

*October 15, 2011 by Daniel*

**Statistics**

Are you annoyed with spam e-mail? Suppose a random sample of 200 Kent State students was asked this question of which 80% said that they are annoyed. From the provided information we can find the following: sample percent = 80% (sample proportion = .80) standard deviation (S.D...

*July 9, 2012 by Sheri*

**math**

Let x1,x2,x3,x4,x5 be random sample of f(x)=(x+1)/2,-1<x<1,zero elsewhere, find P(four of{x1,x2,x3,x4,x5}>0)

*December 28, 2014 by assma*

**math**

Let x1,x2,x3 be random sample of f(x)=exp(-x),x>0,zero elsewhere,if y1=x1/x2,y2=x3/(x1+x2),y3=x1+x2 find g(y1,y2,y3),g(y1),g(y2,y3)

*December 28, 2014 by assma*

**Statistics **

Assume that a random sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level. 95% confidence the sample size is 2096 of which 25%are successes The margin of E= (round to four decimal places ...

*April 30, 2013 by Rob*

**statistics**

homework due by 8am on 2/26...spent too much time with bad websites....still no answers....need help with simple random sample...Have 460 clients...need SRS of 20 clients for survey...Have a number table to select sample from:13873 81598 95052 90908 73592 75186 87136 95761 ...

*February 25, 2007 by nancy*

**statistics**

3. The mean volume of draught beer served in pint glasses in a particular pub is known to be 0.564 litres. A consumer organization takes a random sample of 64 pints of draught beer and finds that the standard deviation of this sample is 0.025 litres. What is the probability ...

*November 5, 2011 by najma*

**Hypothesis Test**

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 120 ...

*November 16, 2013 by Simon*

**Statistics**

In an elementary school, 25% of children wear glasses. Suppose that a random sample of 64 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*June 2, 2013 by Sarah*

**Statistics**

In an elementary school, 25% of children wear glasses. Suppose that a random sample of 64 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*June 2, 2013 by Sarah*

**Statistics**

In an elementary school, 25% of children wear glasses. Suppose that a random sample of 64 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*June 2, 2013 by Sarah*

**Statistics**

In an elementary school, 25% of children wear glasses. Suppose that a random sample of 64 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*June 2, 2013 by Sarah*

**Statistics**

In an elementary school, 25% of children wear glasses. Suppose that a random sample of 64 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*June 2, 2013 by Sarah*

**Stats**

In an elementary school, 29% of children wear glasses. Suppose that a random sample of 31 children is selected. Find the mean number of children in the sample who wear glasses. Round your answer to the nearest integer.

*October 13, 2015 by Semmy*

**statstics**

a report says 65% of vechiles sold were SUV's. A random sample of 100 vechiles sold in last month is taken. Use the central limit theorem, find the probability that most 70% of the vechiles in the sample were SUV's

*August 25, 2014 by bob*

**Math**

When a truckload of apples arrives at a packing plant, a random sample of 250 is selected and examined for bruises, and other defects. The whole truckload will be rejected if more than 5% of the sample is unsatisfactory. Although it is not known, in fact 8% of the apples on ...

*October 8, 2012 by Jonathan*

**Statistics**

When a truckload of apples arrives at a packing plant, a random sample of 250 is selected and examined for bruises, and other defects. The whole truckload will be rejected if more than 5% of the sample is unsatisfactory. Although it is not known, in fact 8% of the apples on ...

*October 8, 2012 by Jonathan*

**statistics**

A study involving the economic burden of congestive heart failure found that the lengths of hospital stays for patients had a mean of 7.8 days with a standard deviation of 9.1 days. For random samples of size 40, find the sample mean length of stay that is smaller than 10% of ...

*May 8, 2013 by ali awan*

**statitics**

Suppose that a sample of n = 1,600 tires of the same type are obtained at random from an ongoing production process in which 8% of all such tires produced are defective. What is the probability that in such a sample 150 or fewer tires will be defective

*March 27, 2012 by Chris*

**statitics**

Suppose that a sample of n = 1,600 tires of the same type are obtained at random from an ongoing production process in which 8% of all such tires produced are defective. What is the probability that in such a sample 150 or fewer tires will be defective

*March 27, 2012 by Chris*

**Math Statistics**

3. Suppose 20% of all heart transplant patients do not survive the operation. a. Think about taking repeated random samples of 371 patients from this population. Describe how the sample proportion who die would vary from sample to sample. (Hint: Be sure to refer to the shape, ...

*July 22, 2013 by TCaesar*

**Math**

Having trouble knowing where to start with this one: A maker of tools claims the average amount of time it takes to assemble a table saw is 50 mins with a standard deviation of 40 mins. What is the probability that the sample mean will be less than 44 mins if a random sample ...

*March 23, 2010 by Len*

**statistics**

From a shipment of 350 batteries, a sample of 125 was selected at random and tested. If 25 batteries in the sample were found to be dead, how many dead batteries would be expected in the entire shipment?

*February 13, 2013 by Anonymous*

**Probability**

A customer at Cavallaro’s Fruit Stand picks a sample of 3 oranges at random from a crate containing 60 oranges, of which 4 are rotten. What is the probability that the sample contains 1 or more rotten oranges?

*July 23, 2016 by Brandon*

**Probability **

A customer at Cavallaro's Fruit Stand picks a sample of 4 oranges at random from a crate containing 50 oranges, of which 4 are rotten. What is the probability that the sample contains 1 or more rotten oranges?

*December 6, 2016 by Bobbie*

**statistics**

Assume a simple random sample has been taken, the conditions for binomial distribution are met and the sample proportions can be approximated by a normal distribution. In order to evaluate a course of therapy to treat brain tumors, a sample of 300 patients revealed that 96 ...

*December 5, 2012 by Ox*

**statistics**

Assume a simple random sample has been taken, the conditions for binomial distribution are met and the sample proportions can be approximated by a normal distribution. In order to evaluate a course of therapy to treat brain tumors, a sample of 300 patients revealed that 96 ...

*December 5, 2012 by Ox*

**Stats**

A dean wishes to estimate the average cost of the freshman year at a particular college correct to within $500, with a probability of 0.95. If a random sample of freshmen is to be selected and each asked to keep financial data, how many must be included in the sample? Assume ...

*December 5, 2016 by Sara*

**statistic****help*******

Show all your work. Indicate clearly the methods you use because you will be graded on the correctness of your methods as well as on the accuracy of your results and explanation. A simple random sample of adults living in a suburb of a large city was selected. The age and ...

*March 19, 2014 by akiba*

**Math**

A vending machine has marbles of 4 different colors: Red, blue, purple,and yellow. The marbles are well mixed. You drop a quarter into the machine and you get 2 random marbles. Write out the sample space for the experiment. The sample space should be N = 10.

*July 11, 2012 by Meredith*

**statistics**

Suppose that large dogs weights are normally distributed with a mean of 100 pounds and a standard deviation of 10 pounds. If one of these dogs is picked random: a) what is the probability that the dog will weigh over 110 pounds? b) what is the probability that the dog will ...

*March 26, 2010 by Anonymous*

**Statistics**

According to one survey, the mean serum cholesterol level for U.S. adults was 195.1, with a standard deviation of 41.5. A simple random sample of 95 adults is chosen. Find the 46 percentile for the sample mean. Write only a number as your answer. Round to one decimal places.

*October 6, 2015 by Tommy*

**maths**

a box contains 20 fuses ,out of which ,5 are defective.if a sample of 3 fuses is chosen from the box at random without replacement,find the probability that x fuses in this sample will be defective

*February 11, 2012 by ashely*

**statistics and probability**

scores on a nationwide professional qualifying exam, have a mean of 600 and a standard deviation of 50.A random sample of 100 examinees was selected.The sample mean was 360.what was the standardized value or z-score of the sample mean in this instance. soln: Z=VALUE-MEAN/...

*December 3, 2015 by masinde*

**statistical applications**

when is random sampling not the best approach to sample selection?

*March 8, 2010 by anette*

**math **

Find the probability between 42 and 48 speeders in a random sample of 100

*May 2, 2013 by john jones*

**STATISTIC***HELP**

Show all your work. Indicate clearly the methods you use because you will be graded on the correctness of your methods as well as on the accuracy of your results and explanation. A simple random sample of adults living in a suburb of a large city was selected. The age and ...

*March 18, 2014 by KIBA*

**statistics**

1. A random sample of size 49 is taken from a large population, measuring the time it takes to complete a driver’s license examination. The sample mean was found to be 47 minutes, and the sample standard deviation 5.89 minutes. Construct a 95% confidence interval around the ...

*July 17, 2010 by Anonymous*

**statistic**

For a given month, a random sample of 30 sales girls from a superstore has a sample mean of salary of RM 800 with standard deviations of RM 140. Estimate the mean monthly salary for all employees using the 95% confidence interval.(what does mean of 95% confidence level?)

*September 27, 2011 by niki*

**statistic**

A final exam in Math 160 has a mean of 73 with standard deviation 7.73. Assume that a random sample of 24 students is selected and the test score of the sample is computed. Assuming the scores are normally distributed, what percentage of sample means are less than 76&#...

*September 11, 2016 by Anonymous*

**Statistics**

I have another Stats question i'm confuesed on. classify the sample as random, systematic, covenience, stratified, or cluster. A marketing executive fo General Motors finds that its public department has just printed envelopes with the names and addresses of all Corvette ...

*January 21, 2013 by Gavin*

**Stats**

Recently, an automobile insurance company performed a study of a random sample of 15 of its customers to determine if there is a positive relationship between the number of miles driven and the age of the driver. The sample correlation coefficient is r=.38. Given this ...

*June 13, 2011 by Breezy*

**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 the ...

*March 16, 2015 by Leo Elvis*

**Math Stats**

Suppose that a random sample of n kernels of popcorn is taken and x of these kernels pop. The buyer wants to be 95% sure that the point estimate for p will be within 0.01.If no preliminary study is done to estimate p, how large a sample should the buyer use? If a preliminary ...

*March 28, 2012 by Apryl*

**Statisics **

I need help on this question i am confused. I don't think the answers i got are right The library checks out an average of 320 books per day, with a standard deviation of 75 books. Suppose a simple random sample of 30 days is selected for observation. What is the probability ...

*February 20, 2011 by Mike*

**AP Stat**

A random sample of 15 people is taken from a population in which 40% favour a particular political stand. What is the probability that exactly 6 individuals in the sample favour this political stand? 0.4000 0.5000 0.4000 0.2066 0.0041

*November 24, 2009 by Cb*

**Math I need help ASAP!**

1. which of the following is true of a random sample? a. it is the only way to sample a population. b. each member of the sample is a volunteer. c. it is always the easiest way to sample a population. d. each member of the population has an equal chance of being selected. 2. ...

*May 27, 2015 by Carolina*

**Statistics**

a laptop manufacturer finds that the average time it takes an employee to load a laptop with software is 20 minutes with a standard deviation 8 minutes. suppose you take a random sample of 81 employees. the standard deviation of the sample mean is?

*October 6, 2014 by Kalyssa*

**stats**

A simple random sample of 30 items resulted in a sample mean of 15. The population standard deviation is σ = 8. Round your answers to two decimal places. a. What is the standard error of the mean, σx? b. At 95% confidence, what is the margin of error?

*April 22, 2016 by Anonymous*

**statistics**

The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 50 students who took the exam is selected for study: A) What is the shape, mean, and ...

*November 6, 2008 by Marshall*

**STATISTICS HELP PLEASE!**

suppose you wish to estimate a population mean based on a random sample of n observations, and prior experience suggests that sd=12.7. if you wish to estimate the mean correct to within 1.6, with probability equal to .95, how many observations should be included in your sample?

*November 15, 2010 by Courtney*

**statistics**

A psychologist wants to estimate the variance of employee test scores. A random sample of 18 scores had a sample standard deviation 10.4. Find a 90% confidence 2 interval for the population variance. What assumption, if any, have you made in calculating this interval estimate?

*November 9, 2011 by Janelle*

**statistics**

The average temperature in households is 67.6 degrees F. The standard deviation is 4.2 degrees F. A random sample of 51 households is to be selected What is the probability that the average of this sample will be within 1.4 STANDARD ERRORS of the population mean?

*September 28, 2012 by Kristin*

**STATISTICS**

The number of boxes of girl scout cookies sold by each of the girl scout in a city has a distribution which is approximately normal with a mean=75 boxes and a standard deviation=30 boxes.... 1.) find the probability that scout chosen at random sold between 60 and 90 boxes. 2...

*August 10, 2011 by Mason*

**Probability and Statistics**

A research psychologist believes that professional athletes tend to be more confident than the typical person. From previous testing, he knows that the scores for people in the general population are approximately normally distributed with a mean of 72 and standard deviation ...

*April 29, 2012 by Kim*

**Statistics 2 please give answers to the below ques**

According to a study conducted by a statistical organization, the proportion of americans who are satisfied with the way things are going in their lives is 0.82. Suppose that a random sample of 105 Americans is obtained. (Please answer the below and round to four decimals ...

*November 26, 2014 by LADO*

**stats of biologists**

a manufacturer claims that the life time of a certain brand of batteries has a varaince of 5000(hours)^2. a sample of 26 has a variance of 7200(hours)^2. assuming that it is reasonable to treat these data as a random sample from a normal population, test the manufacturer's ...

*February 14, 2013 by Aboli*

**Statistics**

A large furniture store has begun a new ad campaign on local television. Before the campaign, the long term average daily sales were $24,819. A random sample of 40 days during the new ad campaign gave a sample mean daily sale of x(bar)=$25,910 with sample standard deviation s...

*May 9, 2012 by Matt*

**Math**

will someone just double check my answers, please. Identify which types of sampling is used:random,stratified, systematic,convenience. 1. a sample consists of every 20th student who leaves the bookstore. answer:systematic 2. a pollster uses a computer to generate 500 random ...

*April 15, 2010 by Charlene*

**math**

A simple random sample of 800 individuals provides 250 Yes responses.

*November 17, 2015 by bob*

**statistics**

A random sample of 384 people in Dalto City, a mid-sized city, revealed 112 individuals who work at more than one job. A second random sample of 432 workers from East Dettweiler, another mid-sized city, found 91 people who work at more than one job. To conduct a significance ...

*October 26, 2012 by Derp*

**statistics**

A random sample of 384 people in Dalto City, a mid-sized city, revealed 112 individuals who work at more than one job. A second random sample of 432 workers from East Dettweiler, another mid-sized city, found 91 people who work at more than one job. To conduct a significance ...

*November 4, 2012 by John*

**Statistics**

A random sample of 384 people in Dalto City, a mid-sized city, revealed 112 individuals who work at more than one job. A second random sample of 432 workers from East Dettweiler, another mid-sized city, found 91 people who work at more than one job. To conduct a significance ...

*November 5, 2012 by John*

**Math**

At your summer with a research company, you must get a random sample of people from your town to answer a question about spending habits. Which of the following Methods is most likely to be random? a)You survey customers at the local shopping mall b)You survey people chosen ...

*May 28, 2014 by Dope Fresh Nation*

**math**

The sample mean to be calculated from a random sample of size n= 4 from a population consistsof eight measurements (2, 6, 9, 12, 25, 29, 39, 50) . find the sampling distribution of y y .(hint : there are 70 samplesof size 4 when sampling from a population of eight measurements )

*November 13, 2010 by heba*

**statistics **

The sample mean to be calculated from a random sample of size n= 4 from a population consists of eight measurements (2, 6, 9, 12, 25, 29, 39, 50) . find the sampling distribution of y .(Hint : there are 70 samples of size 4 when sampling from a population of eight measurements )

*November 14, 2010 by koky*

**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)?

*April 21, 2014 by Vanessa*

**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...

*March 27, 2015 by Anonymous*

**Statistics**

A survey organization takes a simple random sample of 625 households from a city of 80,000 households. On the average, there are 2.30 persons per sample household, and the SD is 1.75. Say whether each of the following statements are True or false and explain (a) The SE for the...

*October 26, 2011 by Joyann*

**Statistics**

How long does it take to have food delivered? A Chinese restaurant advertises that the mean delivery will be no more than 30` minutes. A random sample of delivery times is shown below. Based on this sample data, is the mean delivery time different than 30 minutes? Use a 5% ...

*March 25, 2012 by Jasmine*

**Urgent =Math**

Tell whether this survey describes a good sample and if so, name the method of sampling used. A phone company randomly calls 6 names from the phone book to find whether the person is satisfied with the phone service. yes, random yes, systematic***** yes, stratified not a good ...

*May 6, 2016 by Monica*

**Stats**

It is known that the amount of time needed to change the oil in a car is normally distributed with a standard deviation of 5 minutes. A random sample of 100 oil changes yielded a sample mean of 22 minutes. Compute the 99% confidence interval estimate of the mean of the ...

*February 26, 2007 by Jason L*

**ap stats need help**

Continuous Random Variable, I Let X be a random number between 0 and 1 produced by the idealized uniform random number generator described. Find the following probabilities: a.P(0¡ÜX¡Ü0.4) b.P(0.4¡ÜX¡Ü1) c.P(0.3¡ÜX0.5) d.P(0.3(<X<0.5) e.P(0.226¡ÜX¡Ü0.713) f...

*March 10, 2009 by chris*

**math**

(A) An architect estimates that the average height of the buildings of 30 or more stories in Suva is at least 500 feet. A random sample of 12 buildings is selected, and the heights in feet are shown. At =0.025, is there enough Evidence to reject the claim? 634 385 411 ...

*September 25, 2016 by pamu*

**math**

(A) An architect estimates that the average height of the buildings of 30 or more stories in Suva is at least 500 feet. A random sample of 12 buildings is selected, and the heights in feet are shown. At =0.025, is there enough Evidence to reject the claim? 634 385 411 ...

*September 26, 2016 by oliva*

**stats**

An automobile repair shop has determined that the average service time on an automobile is 2 hours with a standard deviation of 32 minutes. A random sample of 64 out of 400 services is selected. What is the probability that this sample will have a mean service time greater ...

*November 11, 2009 by sandy*

**Statistics**

A university has 1,000 computers available for students to use. Each computer has a 250-gigabyte hard drive. The university wants to estimate the space occupied on the hard drives. A random sample of 100 computers showed a mean of 115 gigabytes used with a standard deviation ...

*October 27, 2013 by Shelby*

**Statistics**

The null and alternate hypotheses are: H0: μ1 = μ2 H1: μ1 ≠ μ2 A random sample of 15 items from the first population showed a mean of 50 and a standard deviation of 5. A sample of 12 items for the second population showed a mean of 46 and a standard ...

*October 21, 2012 by Anonymous*

**Statistics**

Suppose x has a distributionwith u=72 and 0=8 if random samples of size n=16 are selected, can we say anything about the x distributin of sample means if the originalx distribution is normal can we say anything about the x distribution of random samples of size 16 find p(68<...

*June 14, 2010 by John*

**statistics**

Use the given confidence level and sample data to find a confidence interval for the population standard sigma. Assume that a simple random sample has been selected from a population that has a normal distribution. salaries of college graduates who took a geology course in ...

*December 29, 2011 by rich*

**statistics**

List below are the duration (in hours) of a simple random sample of all flights of a space shuttle program. Find the range, variance, and standard deviation for the sample data. Is the lowest duration time unusual? Why or hwy not? 73 95 238 199 166 268 198 374 260 235 382 339 ...

*October 29, 2013 by angela*

**mba business reserach methods**

Sampling A manufacturing company's quality control personnel have recorded the proportion of defective items for each of 500 monthly shipments of one of the computer components that the company produces. See data below. The company doesn't have time to review all of these. (a...

*March 20, 2011 by Carolina*