Saturday

June 25, 2016
**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 by sue spear*

**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 by sue spear*

**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 by charissa*

**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 by yes help me I'm an idiot*

**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 by courtney*

**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 by pat*

**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 by Courtney R*

**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 by Jan*

**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 by Megan*

**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 by Megan*

**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 by Megan*

**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 by alec*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Kim*

**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 by R*

**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 by Micheal*

**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 by Leticia*

**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 by Osa*

**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 by brittany*

**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 by ann*

**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 by Richelle*

**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 by Richelle*

**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 by Anonymous*

**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 by Anonymous*

**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 by Elaine*

**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 by Anonymous*

**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 by lolo*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Anonymous*

**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 by Lizzie*

**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 by Lizzie*

**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 by Lizzie*

**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 by Lizzie*

**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 by Lizzie*

**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 by kelli*

**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 by Nina*

**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 by Taylor*

**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 by Z*

**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 by Anonymous*

**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 by Emily*

**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 by Anonymous*

**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 by Remi*

**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 by etoile*

**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 by jimm*

**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 by ben*

**statistics **

Does a correlation ever prove causation? (For any subject/field?)
*Tuesday, March 17, 2015 by Anonymous*

**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 by lisa*

**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 by Jamie*

**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 by Scott*

**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 by Greg*

**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 by Hannah*

**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 by Hannah*

**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 by Cara*

**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 by Amy*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**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 by Leo Elvis*

**Statistics**

How many different ways can you put 3 distinguishable things in 10 boxes?
*Saturday, March 14, 2015 by Bob*

**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 by madi*

**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 by slomomo*

**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 by Howard*

**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 by Cindy*

**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 by Cindy*

**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 by mary ann*

**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 by slomomo*

**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 by chris*

**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 by stuart joel*

**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 by jesse*

**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 by Anon*

**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 by Leatha*

**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 by Nicole*

**statistics **

Z-test. How to find critical value for one tail test?
*Tuesday, March 10, 2015 by Anonymous*

**statistics - can someone please Help me**

I have tried for days to figure out how to work this problem. Please help show me how to find the answer. A particular radioactive isotope decays from 210 mg to 182.7 mg in 15 days. Find the half life of the isotope. I can not find any problem that is similar. everything i ...
*Tuesday, March 10, 2015 by Tina*

**statistics **

How to find p value? If test statistic is -0.37, will the p value be 0.3557?
*Tuesday, March 10, 2015 by Anonymous*

**statistics**

I have tried for days to figure out how to work this problem. Please help show me how to find the answer. A particular radioactive isotope decays from 210 mg to 182.7 mg in 15 days. Find the half life of the isotope.
*Tuesday, March 10, 2015 by Tina*

**statistics**

A jar contains 3 nickels and 2 dimes. You reach in and randomly select 2 coins. Let x represent the value of the two coins in cents. Find the expected value and standard deviation of x
*Tuesday, March 10, 2015 by Ashley*

**statistics**

Determine whether the description corresponds to an observational study or an experiment. Research is conducted to determine if there is a relation between kidney function in adults and childhood-onset diabetes.
*Tuesday, March 10, 2015 by slomomo*

**statistics**

Based on a study of IQs of men and women who play chess competitively, a researcher concludes that playing chess causes people to become smarter. Do you agree with this conclusion?
*Tuesday, March 10, 2015 by slomomo*

**Statistics**

A history class is comprised of 5 female and 8 male students. If the instructor of the class randomly chooses 8 students from the class for an oral exam, what is the probability that 2 female students and 6 male students will be selected? Round your answer to decimal places.
*Tuesday, March 10, 2015 by Ryan*

**problem and statistics**

In a random sample of 10 on-line statistics students, information was collected about their minutes studied and their chapter test scores. X is the minutes studied, and Y is the test score. x : {20,30,45,60,80,90,45,120,90,70} y: {50,45,55,70,80,90,80,100,95,85} Is this ...
*Monday, March 9, 2015 by Zikera*