Thursday
July 31, 2014

Homework Help: Math: Statistics

Recent Homework Questions About Statistics

Post a New Question | Current Questions

statistics
If the average number of textbooks is 16, the standard deviation is 5, and the average age of a professors is 43, with a standard deviation of 8, which data set is more variable?
Sunday, March 10, 2013 at 3:50pm

Statistics
Suppose. Population of test-scores is normally distributed with mean 65 and standard deviation 13 x~n (65,13) if you select a test at randome what is the probability that the score is below 60 or that it is between 65 and 70 please show work!
Sunday, March 10, 2013 at 3:38pm

Statistics
"Working Mom’s Journal" reported that the mean time a mother, with her small children, spends in at the convenience store is 7.3 minutes. A sample of 20 moms is chosen from your neighborhood, and it is found that the mean time they spend in a convenience store ...
Sunday, March 10, 2013 at 1:30pm

Statistics
A private opinion poll is conducted for a politician favors decriminalizing marijuana possession. How large a sample is needed in order to be 95% confident that the sample proportion will not differ from the true proportion by more than 2%.
Sunday, March 10, 2013 at 3:38am

statistics
a towns average snowfall is 33 inches per year with a standard deviation of 11 inches. how many standard deviations from the mean is a snowfall of 66 inches
Saturday, March 9, 2013 at 10:16pm

statistics(HELP)ASAP
an art school knows that in general they go through 38 colored pencils per week. they have asked their students to hold their pencils differently over the past 10 weeks and wonder whether this has made a significant difference in the number of penccils they go through. dat aon...
Friday, March 8, 2013 at 11:34pm

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 ...
Friday, March 8, 2013 at 9:35pm

statistics(HELP)ASAP
an art school knows that in general they go through 38 colored pencils per week. they have asked their students to hold their pencils differently over the past 10 weeks and wonder whether this has made a significant difference in the number of penccils they go through. dat aon...
Friday, March 8, 2013 at 9:33pm

Statistics
A nurse at a local hospital is interested in estimating the birth weight of infants. How large a sample must she select if she desires to be 99% confident that the true mean is within 2 ounces of the sample mean? The standard deviation of the birth weights is known to be 7 ...
Friday, March 8, 2013 at 5:09pm

statistics
s = sqrt { [ 9 + 1 + 1 + 9 ] / 3 } = sqrt (20 / 3) = sqrt ( 6.67 ) = 2.58 how they get the 2.58
Friday, March 8, 2013 at 3:54am

Statistics
The 60th percentile of a normal distribution is 110. The 70th percentile is 120. Find the 90th percentile.
Thursday, March 7, 2013 at 10:23am

Statistics
Find the 35th percentile of the normal distribution with mean 270 and SD 25.
Thursday, March 7, 2013 at 10:23am

Statistics
Fill in the blank: 50% of the area under the standard normal curve is between -0.5 and _____________.
Thursday, March 7, 2013 at 10:22am

Statistics
The average weight of a group of people is 156 pounds and the SD is 25 pounds. A statistician wants to transform the weights so that the transformed weights have an average of 100 pounds and an SD of 10 pounds. Fill in the blanks; both blanks must be filled in correctly for ...
Thursday, March 7, 2013 at 10:21am

Statistics
In the quiz in Exercises 1 and 2, the grading scheme is as follows: each right answer is awarded 5 points, and 1 point is taken off for each wrong answer. Recall that the quiz consists of 10 questions, and that in the class, the average number of right answers is 6.2 and the ...
Thursday, March 7, 2013 at 10:20am

Statistics
A quiz consists of 10 questions. Each question is marked either “right” or “wrong.” For each student in the class, the instructor keeps a record of the number of right answers the student got. In the class, the average number of right answers is 6.2 and the...
Thursday, March 7, 2013 at 10:10am

Statistics
A list of numbers has an average of 48 and an SD of 12. The list is transformed by subtracting 3 from each entry and then dividing the result by 5. (1) Find the average of the transformed list. (2) Find the SD of the transformed list.
Thursday, March 7, 2013 at 10:09am

Statistics
Using the following Minitab output write the straight line (least squares) equation and the correlation coefficient. The regression equation is Sales = 27.2 + 0.252 Exp Predictor Coef SE Coef T P Constant 27.195 5.781 4.70 0.005 Exp 0.2517 0.4201 0.60 0.575 S = 8.97833 R-Sq = ...
Wednesday, March 6, 2013 at 7:06pm

statistics
In a survey randomly selected subjects, the mean age of the 36 respondents is 40.0 years and the standard deviation of the ages is 10.0 years. Use these sample results to construct a 95% confidence interval estimate of the mean age of the population from which the sample was ...
Wednesday, March 6, 2013 at 1:21pm

statistics
Assume that we collect a large (n>30) simple random sample of annual incomes of adults in the United States. Because the sample is large, can we approximate the distribution of those incomes with a normal distribution ? Why or why not?
Wednesday, March 6, 2013 at 1:10pm

Statistics
The rate of chlamydia infection was reported as 2.78% in a recent year. Under certain conditions, a preliminary screening test for the chlamydia bacterium is correct 96% of the time. One person is randomly selected from the population. find the true positive. Can someone ...
Wednesday, March 6, 2013 at 9:56am

Business Statistics
1.  Suppose that the mean of the annual return for common stocks from 1950 to 2012 was 9.4%, and the standard deviation of the annual return was 17.5%.  Suppose also that during the same 62-year time span, the mean of the annual return for long-term government bonds ...
Wednesday, March 6, 2013 at 9:34am

statistics
A balloon mannufacturer kows that historically her company has produced 614 balloons per day (standard deviation =36) she has changed the process and wants to know wheathert he new process is increased the number of ballons made. the sample mean is 620. 0.5, n=16
Tuesday, March 5, 2013 at 9:47pm

statistics
The average admission charge for a movie is $6. if the distribution of movie admission charges is approximately normal with a standard deviation of $1, what is the probability that a randomly selected admission charge is less than $3.5?
Tuesday, March 5, 2013 at 7:14pm

Math Statistics
The hieght of women are approximately normally distributed with a mean of 65.4 inches and a standard deviation of 2.5 inches. What percent of these women would be over 70 inches or more? 70-64.5/2.5 = 2.2 Is this correct? How would I determine the hieghts of the shortest 8% of...
Tuesday, March 5, 2013 at 7:07pm

Statistics
An April 15, 2002 report in Time Magazine stated that the average age for women to marry in the United States is now 24.5 years of age. If the standard deviation is assumed to be 4.1 years, find the probability that a random sample of 32 U.S. women would show a mean age at ...
Tuesday, March 5, 2013 at 1:52pm

stats
Which test do you use to solve this problem One-sample or independent samples t-test? Over the summer I asked my statistics students to report their gender and their level of statistics anxiety. Using a one-tailed test, determine whether females have more statistics anxiety ...
Tuesday, March 5, 2013 at 12:11pm

stats
Which test do you use to solve this problem One-sample or independent samples t-test? Over the summer I asked my statistics students to report their gender and their level of statistics anxiety. Using a one-tailed test, determine whether females have more statistics anxiety ...
Tuesday, March 5, 2013 at 12:11pm

statistics
An April 15, 2002 report in Time Magazine stated that the average age for women to marry in the United States is now 25.1 years of age. If the standard deviation is assumed to be 4.6 years, find the probability that a random sample of 34 U.S. women would show a mean age at ...
Tuesday, March 5, 2013 at 9:32am

statistics
*Give all probabilities to four decimal places. Bowl #1 contains 4 grape candies, 5 lemon candies, 6 cherry candies and 5 raspberry candies. Bowl #2 contains 8 grape candies, 5 lemon candies, 4 cherry candies and 3 raspberry candies. (c) What is the probability that the two ...
Monday, March 4, 2013 at 8:34pm

statistics
Bowl #1 contains 4 grape candies, 5 lemon candies, 6 cherry candies and 5 raspberry candies. Bowl #2 contains 8 grape candies, 5 lemon candies, 4 cherry candies and 3 raspberry candies. (c) What is the probability that the two selected candies are the same flavour? (d) What ...
Monday, March 4, 2013 at 8:08pm

Statistics
A company that manufactures exercise machines wanted to know the percentage of large companies that provides on-site health club facilities. A sample of 240 such companies showed that 96 of them provide such facilities on site. a. What is the point estimate of the percentage ...
Monday, March 4, 2013 at 4:04pm

statistics
Percentage grades in a large physics class follow a normal distribution with mean 58. It is known that 3% of students receive grades less than 39.2. What is the standard deviation of grades in the class?
Monday, March 4, 2013 at 1:39pm

statistics
Is "42% of the people in New York City have 0+ blood" desriptive or inferential?
Monday, March 4, 2013 at 10:34am

statistics
8) Why did you choose this figure as the warranty? What percentage of bulbs would need to be replaced if you chose a warranty of 7000 or 7500? Justify your answer statistically. How do you explain this to the board of directors, marketing people and financial people?
Sunday, March 3, 2013 at 9:50pm

statistics
7) Your employer, Woodbridge Electric Inc., wants to offer a warranty on the new compact fluorescent light bulb that they have produced and tested. You are called into a meeting and operational experts provide the following data: mean bulb life = 8000 hours, standard deviation...
Sunday, March 3, 2013 at 9:49pm

math
As South Campus, the student-faculty ration is about 16 to 1. If the 128 students enroll in Statistics 101, how many sections should be offered?
Sunday, March 3, 2013 at 9:45pm

Statistics
A multiple choice test has five choices. Therefore the probability of getting the correct answer by guessing is 0.2. The test has six questions. Use the binomial formula with n = 6 and p = 0.2 to (a) Determine probability of getting two questions correct. (b)Determine ...
Sunday, March 3, 2013 at 7:22pm

Statistics
The heights of young women are approximately normally distributed with a mean of 64.5 inches and a standard deviation of 2.5 inches. Determine the following: what percent of young women would be acceptable as members if being a member required a height of 70 inches or more? ...
Sunday, March 3, 2013 at 7:20pm

statistics
In order to plan for parking and transportation needs at a college, administrators asked students how they got to school. Some came by bus, some came by car and the others used “personal “ transportation – bikes, skateboards, or walked. The following table ...
Sunday, March 3, 2013 at 7:18pm

statistics
about what percent of the bags of pet food weigh less than 49.8 lb?
Sunday, March 3, 2013 at 3:00pm

statistics
Given that the general population is normally distributed on a standard scale measuring math aptitude with Mean = 50 (s.d. = 10), approximately what percentage of the population has a math aptitude score between 40 and 60?
Sunday, March 3, 2013 at 1:16pm

Math Statistics
1. How many ways can you possibly have if you bet on a single number if there are 38 possible number of choices you have? 2. How many winning combinations can you have when you have 12 numbers to choose from out of 38?
Sunday, March 3, 2013 at 9:44am

Statistics
Suppose that 7.6% of all people are allergic to the H1N1 vaccine. A sample of 517 people are selected a. Calculate the probability that less than 8% of the sample will be allergic to vaccine.
Sunday, March 3, 2013 at 4:53am

statistics
The composition of the 108 congress was 51 republican 48 democrats and 1 independent.a committee on aid to higher education is to be form with 3 senators to be chosen random to head the committee. find the probability that the group of 3 consist of, all republicans , all ...
Saturday, March 2, 2013 at 5:53pm

statistics
The U.S. Census Bureau reported 77% of the U.S population had internet access in 2009. Choosing 3 random individuals find the probability that a. none of the 3 inidivuals has internet b. all of the individuals have internet access c. at least 1 of the 3 individuals has ...
Saturday, March 2, 2013 at 4:28pm

Statistics
DIAGRAMS MUST BE DRAWN Given the standard normal distribution, determine:Prob Z greater than 1.50 Prob Z between1.06 and 1.96 Given the standard normal distribution determine the Z values that contain 80% in the middle of the curve.
Saturday, March 2, 2013 at 2:51pm

Statistics
This is a standard deviation contest. You have a six sided die with the numbers 1 to 6 written on the faces. a)In order to have the smallest possible standard deviation what number(s) would have to show up if you rolled the die five times? b)In order to have the largest ...
Saturday, March 2, 2013 at 2:46pm

statistics
Boxes of bran flakes are known to be normally distributed with a mean weight of 475g and a standard deviation of 10g.Calculate the probability of a box having a weight exceeding 485 grams. Calculate the probability that the mean weight of sixteen boxes will exceed 480g.
Saturday, March 2, 2013 at 2:43pm

Statistics
Consider a basketball game where a player throws from the free throw line. Her success rate is 65%. If she throws 10 times in a game determine the following:The mean and standard deviation of this binomial distribution.
Saturday, March 2, 2013 at 2:39pm

Statistics
2. (TCO 5) A company produces electronic equipments claims that 98% of their products never need any kind of maintenance. We selected 10 of their products and we wanted to know the probability that 8 of them never need maintenance. Choose the best answer of the following: (...
Friday, March 1, 2013 at 9:57pm

math-statistics
Assume the body temperature of healthy adults are normally distributed with a mean of 98.20 degrees F (based on data from the Uniservity of Maryland researchers).a. If you have a body temperature of 99.oo degrees F, what is your percentile score? b. Convert 99.00 degrees F to ...
Friday, March 1, 2013 at 6:58pm

Math-statistics
Assume that a set of test scores is normally distributed with a mean of 100 and a standard deviation of 20. Use the 68-95-99.7 rule to find the following quantiles: a.percentage of scores less than 100 b. relative frequency of scores less than 120 c. percentage of scores less ...
Friday, March 1, 2013 at 6:31pm

statistics
I am seeing some inconsistencies with regards to finding the upper and lower quartiles when you you have an odd number in your data set. Which is correct, counting the median in both your upper and lower set, or ignoring it?
Friday, March 1, 2013 at 5:40pm

statistics
A residential treatment facility tests a new group therapy for patients with self destructive behaviors. To decrease scores of behaviors that has a mean in the overall population of 35 and a standard deviation of 4.7. The mean score for patients after new group therapy is 27. ...
Friday, March 1, 2013 at 3:37pm

statistics
#1: Total students 237, total males 41, need to estimate the proportion of students that are male using 90% confidece level. Also #2: estimate the proportion of students that commute less than 5 miles to work within 2% , what sample size would you need. Total students 237. ...
Friday, March 1, 2013 at 2:55pm

STATISTICS
I need help with 2 questions-TODAY-HELP 8. Assume that the MM207 Student Data Set is a random sample of all Kaplan students; estimate the proportion of all Kaplan students who are male using a 90% level of confidence. 9. Assume you want to estimate with the proportion of ...
Friday, March 1, 2013 at 10:59am

Criminology Statistics
A given distribution has a mean of 60. A score of 75 had a corresponding z of +2.00. The standard deviation is
Friday, March 1, 2013 at 10:44am

Statistics
Find the average of the distribution given below. Value Percent of entries -16 10 -3 25 5 45 8 20
Friday, March 1, 2013 at 8:08am

Statistics
A firm has 82 employees. The average commute distance (that is, the travel distance from home to work) of the employees is 6.2 miles. How many employees have a commute distance of less than 15.5 miles? Select all that are correct. more than 25 more than 35 more than 45
Friday, March 1, 2013 at 8:06am

Statistics
A real estate company is selling 32 houses. One of the houses costs $834,000, but in order to attract more buyers, the price is dropped to $819,000. By how much does this change the average price of the 32 houses?
Friday, March 1, 2013 at 7:24am

Statistics
As part of a fund raising campaign, the 12 members of the governing board of an organization pledge to raise $100,000. In the first month of the campaign, the average amount raised by the 12 board members is $5,200. How much more must they raise, on average, so that they can ...
Friday, March 1, 2013 at 7:23am

StatIstics
"Household size" is defined as the number of people living in a household. In a sample of 1200 households in California in 2010, the average household size was 2.9 people. Which of the following conclusions can be drawn from this information? Select all that are ...
Friday, March 1, 2013 at 7:21am

statistics
The SAT scores of a certain population of students are approximatley normally distributed with a mean and standard deviation of 1000 and 200 points, respectively. the probabilalty that a student selected at random from the population has an SAT score between 800 and 1200 is?
Thursday, February 28, 2013 at 1:49pm

statistics
Assume you want to estimate with the propoportion of student who commute less than 5 miles to work(20) with in 2%, what sample size would you need. Total in survey is 233
Thursday, February 28, 2013 at 12:38pm

statistics
Using the average and standard devation for length variable from problem 3,find the probability that the length of 35 movies is less than 120 minutes. Assume the distribution is normally distributed. interpret your result.
Wednesday, February 27, 2013 at 6:46pm

Statistics
What sample size is needed to find the percent of the customers at a store that are married, if 90% confidence is desired to be within a 5% margin of error?
Wednesday, February 27, 2013 at 12:05pm

statistics
A professional employee in a large corporation receives an average of = 45 e-mails per day. Most of these e-mails are from other employees in the company. Because of the large number of e-mails, employees find themselves distracted and are unable to concentrate when they ...
Wednesday, February 27, 2013 at 9:35am

statistics
Suppose a random sample of 80 measurements is selected from a population with a mean of 65 and a variance of 300. Select the pair that is the mean and standard error of x.
Tuesday, February 26, 2013 at 4:04pm

statistics
Suppose a random sample of 80 measurements is selected from a population with a mean of 65 and a variance of 300. Select the pair that is the mean and standard error of x.
Tuesday, February 26, 2013 at 4:03pm

Statistics
A simple random sample of 120 SAT scores ahs a mean of 1540. Assume that SAT scores have a population standard deviation of 333. a) Construct a 95% conf. interval estimate of the mean SAT score. b) Is a 99% conf. interval estimate of the mean SAT score wider than the 95% conf...
Tuesday, February 26, 2013 at 1:16pm

Statistics
Out of 4 architects, 6 engineers and 9n electricians, how many ways can a group of 6 people be formed to attend a forum if there are at least 3 electricians?
Monday, February 25, 2013 at 7:17pm

Statistics
Is it appropriate to call the numbered lock combination in our doors and drawers a "combination?" Explain.
Monday, February 25, 2013 at 7:16pm

statistics
The average height for Chinese women is 62.5 inches with a standard deviation of 4.6 inches. What is the probability that a randomly selected woman in the United States would be ≥69 inches tall?
Monday, February 25, 2013 at 6:14pm

statistics
In a certain region, the mean annual salary for plumbers is $51,000. Let x be a random variable that represents a plumber's salary. Assume the standard deviation is $1300. If a random sample of 100 plumbers is selected, what is the probability that the sample mean is ...
Monday, February 25, 2013 at 11:14am

statistics
the breaking distance of a Honda CRV can be approximated by a normal distribution, where the mean is 53 meters and the standard deviation is 3.8 meters. Let x be a random variable that represents a braking distance. Find the probability that a randomly selected braking ...
Monday, February 25, 2013 at 11:09am

Statistics
Problem 4 Refer to the box plots in Problem 3. : 4.0 points Compare experiments 4 and 5. When drawn on the same scale, the histogram for one of them has a noticeably higher peak the histogram for the other. From the box plots alone, can you tell which one has the higher peak? ...
Monday, February 25, 2013 at 3:31am

Statistics
Problem 7 Refer again to the table in Problem 6. : 3.0 points Fill in the value of the missing entry.
Monday, February 25, 2013 at 3:30am

Statistics
Problem 6 A histogram shows the number of hours students spent preparing for a test. The table below gives the intervals and the heights of the bars (in percent per hour). Intervals contain the left endpoint but not the right. No student spent 25 hours or more in preparation. ...
Monday, February 25, 2013 at 3:30am

Statistics
Problem 5 In a histogram of lengths measured in millimeters, the height of the 20-40 bar is 1 percent per millimeter. If I measure all the lengths in centimeters instead, then the corresponding bar would be labeled 2-4. : 5.0 points The height of this bar would be: 1 percent ...
Monday, February 25, 2013 at 3:29am

Statistics
Problem 1 The distribution of ages in the United States in the year 2010 is given below. Intervals include the left endpoint but not the right; the number of people aged 100 or more was not zero but it was so small that it makes no difference to the table. You can assume that ...
Monday, February 25, 2013 at 3:27am

Statistics
The distribution of ages in the United States in the year 2010 is given below. Intervals include the left endpoint but not the right; the number of people aged 100 or more was not zero but it was so small that it makes no difference to the table. You can assume that the ages ...
Monday, February 25, 2013 at 3:26am

Statistics
Here is a distribution you have seen before, in Exercise Set 2. It is the distribution of ages in the United States in the year 2010 is given below. Intervals include the left endpoint but not the right; the number of people aged 100 or more was not zero but it was so small ...
Monday, February 25, 2013 at 3:25am

P Value Math Statistics
Find the P-value for the indicated hypothesis test with the given standardized test statistics, z. Decide whether to reject H0 for the given level of significance a. two-tailed test with test statistic z= -1.57 and a=0.04
Sunday, February 24, 2013 at 11:23pm

Statistics
Which of the following is an accurate description of Simpson's paradox? When groups of data are aggregated, an association can get stronger because of a confounding variable. That confounding variable is usually the number of observations in different groups of data. When ...
Sunday, February 24, 2013 at 11:07pm

statistics
In a normal distribution with mu = 25 and sigma = 3, what number corresponds to z = -3? is it 16, 18, or 20
Sunday, February 24, 2013 at 9:17pm

statistics
how to find the tatge cf when using the score at a given percentile ?
Sunday, February 24, 2013 at 3:09pm

statistics
how to find the target cf when using the formula for score at a given percentile ?
Sunday, February 24, 2013 at 3:06pm

statistics
A store manager claims that the average age of his customers is less than 40 years old, while the industry average is 40 years old. He asks you to test his thinking. You collect a sample of 50 customers and found that the average age is 38.7. Assuming that the population ...
Sunday, February 24, 2013 at 1:15pm

statistics
Accuracy of price scanners at Wal-Mart. The National Institute for Standards and Technology (NIST) mandates that for every 100 items scanned through the electronic checkout scanner at a retail store, no more than 2 should have an inaccurate price. A recent study of the ...
Sunday, February 24, 2013 at 12:32am

statistics
Accuracy of price scanners at Wal-Mart. The National Institute for Standards and Technology (NIST) mandates that for every 100 items scanned through the electronic checkout scanner at a retail store, no more than 2 should have an inaccurate price. A recent study of the ...
Saturday, February 23, 2013 at 11:33pm

Math Statistics
The sorting algorithm known as bogosort can be described in pseudocode as: while not isSorted(input): shuffle(input) If we feed bogosort a shuffled array of length n of unique items the distribution of the number of times bogosort checks if the array is sorted (...
Saturday, February 23, 2013 at 8:52pm

statistics
approximately 300 millions golf balls were lost in the united states in 2009 assume the number of gold balls lost in an 18 hole is distributed as a poisson random variable with a mean of 5 balls
Saturday, February 23, 2013 at 12:51am

statistics
For a population of μ = 70 and σ = 20, find the z-score and percentile rank for each of the following X scores: 80, 100, 65, 40.
Friday, February 22, 2013 at 10:13pm

statistics
What is the standard deviation of 31 sample values with a mean of 2954?
Friday, February 22, 2013 at 11:47am

science
3. In a sample of 64 students given an examination in statistics, it is found that the mean weight is 57 kg with standard deviation 9 kg. Find : Ć i) The proportion of students weight 48-62 kg. Ć ii) The proportion of those less than 72 kg. Ć ...
Friday, February 22, 2013 at 7:04am

statistics
otorola discovered that the average defect rate for parts produced on an assembly line varies from run-to-run and is approximately normally distributed with a mean equal to 3 defects per million. Assume that the goal at Motorola is for the average defect rate to vary no more ...
Friday, February 22, 2013 at 1:10am

statistics
what is percentage of scores between37.5 and 39
Thursday, February 21, 2013 at 10:00pm

Statistics
Which of the following is an accurate description of Simpson's paradox? When groups of data are aggregated, an association can get stronger because of a confounding variable. That confounding variable is usually the number of observations in different groups of data. When ...
Thursday, February 21, 2013 at 12:38am

statistics
A sum of twelve given a pair of sixes. give explanation
Wednesday, February 20, 2013 at 12:22pm

Pages: <<Prev | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | Next>>

Post a New Question | Current Questions

Homework Help: Math

Search
Members