# Homework Help: Math: Statistics

## Recent Homework Questions About Statistics

**statistics**

The trends in international mathematic and science study (TIMSS) in 2007 examined eighth grade proficiency in math and science. The mean mathematics scale score for the sample of eighth grade students in the US was 508.5 with a standard error of 2.83. Construct a 95% ...

**statistics**

Salaries for various positions can vary significantly depending on whether or not the company is in the public or private sector. The U.S. department of labor posted the 2007 mean salary for human resource managers employed by the federal government, as &76, 503. Assume the ...

**statistics**

Conduct a chi square analysis to determine whether sex and year in college are related. I have tried to submit the data but I can't seem to make the submission work. For my data I used 20 males and 20 females. and for the year in college I have 10 freshman, 10 sophomore, 10 ...

**statistics**

The following list is a sampling of the costs of various statistics textbooks used at several colleges. Give the upper confidence limit for a 95% confidence interval estimate for the mean cost of all statistics textbooks. 109.95; 92.00; 96.70; 84.85; 92.60; 84.45; 90.95; 77.00...

**Statistics**

In hypothesis testing, as the a level gets smaller, the level of confidence increases. True or False? And why or why not?

**statistics**

In order to subject their cash registers to random audit, suppose we want to select a random sample of three people from this group of cashiers. Bonita, Chandra, Earl, Glenda, Homer, Jamal, Kendra, Maria, Oscar, Reshonda. How do I use a random number table?

**statistics**

A researcher wishes to estimate the proportion of adults living in rural areas who own a gun. He wishes to achieve a margin of error of 2.8%. What is the minimum sample size needed?

**statistics**

The distribution of students’ heights in a class of 100 students is normal, with a mean height of 66 inches and a standard deviation of three. With these parameters, answer the associated question(s). The shortest 10% of the class is equal to or shorter than __________ ...

**statistics**

A student of the author surveyed her friends and found that among 20 males, 4 smoke and among 30 female friends, 6 smoke. Give two reasons why these results should not be used for a hypothesis test of the claim that the proportions of male smokers and female smokers are equal...

**Statistics**

How would I solve each system by substitution? I know basically what to do, but I keep getting stuck. Thanks! 1)x=2-y 3x-2y=1 2)2x+3y=-1 x=y-13

**Statistics**

I need some help on how to write constraints. For example, I don't get how to do these problems and write a constraint for them: 1) A food store owner buys turkeys and hams. The owner plans to purchase at most a total of 50 products. Write a constraint. 2) The food store owner...

**Statistics**

Express the confidence interval (0.033,0.099) in the form of P-E<p<P+E

**Statistics**

Express the confidence interval (0.033,0.099) in the form of P-E<p<P+E

**statistics**

Scores for men on the verbal portion of the SAT-1 test are normally distributed with a mean of 509 and a standard deviation of 112. If a man is randomly selected, find the probablity that his score is at least 571

**Statistics**

Do you drink the recommended amount of water each day? Most Americans don't! On average, Americans drink 5.4 eight-oz servings of water a day. A sample of 36 education professionals was randomly selected and their water consumption for a 24-hour period was monitored; the mean ...

**Statistics**

Express the confidence interval using the indicated format. Express the confidence interval -0.129 < p < 0.631 in the form of p ± E.

**Statistics**

Blood samples from 10 persons were sent to each of two labs for cholesterol determination. The measurements are recorded below: Table 1. Serum Cholesterol measurements of Lab 1 and Lab 2 Subject Lab 1 Lab 2 1 296 318 2 268 287 3 244 260 4 272 279 5 240 245 6 244 249 7 282 294 ...

**Statistics**

Hi, Could anyone help me please, because I'm not sure with my answer, Thank you so much for your help and value time. Blood samples from 10 persons were sent to each of two labs for cholesterol determination. The measurements are recorded below: Table 1. Serum Cholesterol ...

**statistics**

In a batch of 8,000 clock radios 5% are defective. A sample of 14 clock radios is randomly selected without replacement from the 8,000 and tested. The entire batch will be rejected if at least one of those tested is defective. What is the probability that the entire batch will...

**statistics**

Hi, Could anyone help me please, because I'm not sure with my answer, Thank you so much for your help and value time. Blood samples from 10 persons were sent to each of two labs for cholesterol determination. The measurements are recorded below: Table 1. Serum Cholesterol ...

**statistics**

Wages and salaries make up only part of a total compensation. Other parts include paid leave, health insurance, and many others. In 2007, wages and salaries among manufacturers in the United States made up an average of 65.8% of total compensation. To determine if this changed...

**Statistics/Probability**

A component is rejected if its has a diameter less than 70mm, reworked if the diameter is between 70 and 73.5mm or more than 78.5mm. The diameter of a component is normally distributed with a mean 76mm and standard deviation 2.5mm. In a batch of 400 components, determine the ...

**college statistics**

The CEO of ABC manufacturing commissioned a study to look at the differences between the current salaries of her employees (n = 474) and their starting salaries. The study collected current and beginning salary data for each of the 474 employees and the researcher conducted a ...

**statistics**

According to the MIT Airline Data Project, American Airlines controlled 15.5% of the domestic market in 2010. A random sample of 125 domestic passengers that year was selected. Using the normal approximation to the binomial distribution, what is the probability that more than ...

**statistics**

what sampling strategies can be used if the maximum number of students she can include for her survey of 400 and the maximum number of students she can include for her interviews is 20.”

**statistics**

Construct a 95% prediction interval for the number of hours of sleep for an adult who is 45 years old

**statistics**

Suppose a study is done in which several random samples of people from a population are taken and polled on the number of hours per night they sleep. It is determined that the sample proportion for those who sleep at least 8 hours a night is 36%, and the 95% confidence ...

**Introduction to statistics**

A researcher would like to estimate the population proportion of adults living in a certain town who have at least a high school education. No information is available about its value. How large a sample size is needed to estimate it to within 0.19 with 99% confidence? n= (...

**statistics**

the daily milk production for a certain type of dairy cow has a mean of 43 pounds per day with a standard diviation of 5 pounds per day. Suppose this daily mild production has a normal distribution. Calculate the probability that a randomly selected cow of this type has a ...

**Statistics/Probability**

5) The product is sold in packets whose masses are normally distributes with mean of 1.42 kg and a standard deviation of 0.025 kg. (1) Find the probability that the mass of a packet, selected at random, lies between 1.37 kg and 1.45 kg

**Statistics/Probability**

A factory produces a particular type of electronic component. The probability of a component being acceptable is 0.95. The components are packed in boxes of 24. (i) Calculate the probability that a box, chosen at random, contains exactly 22 acceptable components. All the boxes...

**Statistics/Probability**

In the production of a particular model of cell phones, it is found that 5% are defective. Cellular phones are selected at random and put into boxes of 10. If a box is selected at random, find the probability that it contains. (i) Exactly three defective phones (ii) Less than ...

**Statistics/Probability**

The standard deviation of the masses of articles in a large population is 4.55 kg. Random samples of size 100 are drawn from the population. Find the probability that a sample mean will differ from the population mean by less than 0.8 kg.

**Statistics/Probability**

Each day a bakery delivers the same number of loaves of bread to local shop on the corner. On average the shop sells 75% of loaves. Assuming that the number of loaves sold per day has binomial distribution with a standard deviation of 9. Find the number of loaves the shop ...

**statistics**

A committee of three people is to be formed. The three people will be selected from a list of five possible committee members. A simple random sample of three people is taken, without replacement, from the group of five people. Using the letters A, B, C, D, E to represent the ...

**statistics**

assuming that you wished to have the highest possible score on an exam relative to ht e other scores, would you rather have a score of 70 on a test with a mean of 60 and a standard deviations of 5.2 or a score of 81 on a test with a mean of 79 and a standard deviation of 7.1?

**Measurements & statistics in Kinesiology**

In a class of 34 students, how many of them will have a z-score above 1.0?

**statistics**

M&M’s The candy company claims that 10% of the M&M’s it produces are green. Suppose the candies are packed at random into small bags containing about 25 M&M’s per bag. A class of elementary students learning about percentages opens several bags, counts the various colors...

**statistics**

M&M’s The candy company claims that 10% of the M&M’s it produces are green. Suppose the candies are packed at random into small bags containing about 25 M&M’s per bag. A class of elementary students learning about percentages opens several bags, counts the various colors...

**statistics**

a brand name has a 50% recognition rate assume the owner of the brand wants to verify that rate by beginning with a small sample of 5 randomly selected consumers the probability that exactly 4 of the 5 consumers recognize the brand name

**statistics**

A doctor wants to know if her patients are happy with her. She decides to survey a sample of her clients. What method would be best for choosing a random sample that is a fair representation of her patients? A. Assign numbers to each patient and then use a random number ...

**statistics**

a rocket club makes its own rockets. The rockets go to a mean height of 1100 feet with a standard deviation of 60 feet. if the club fires 36 rockets, what is probability that the mean heights of the rockets will be greater than 1080p feet

**statistics**

the heights of the "basketball fans" at a highly anticipated basketball game.

**psy 315**

using the 5 steps of hypothesis testing begining salary mean =17,016,09,sd7.870 and current salary mean= 34,419.5,7 sd=17,075 with n=474 of employees test statistics = 33.036,p<.05

**math 200 statistics**

ADHD a researcher studying ADHD among teenagers obtains a simple random sample of 100 teenagers aged 13 to 17 and asks them whether or not they have ever been prescribed medication for ADHD. To say that the distribution of sample proportion (P cap), the sample proportion of ...

**Statistics**

A COMMITTEE OF 5 PEOPLE IS TO BE FORMED FROM 15 PARENTS AND 10 teachers. Find the probability that the committee will consist of at least one parent.

**Statistics/probability**

The random variable X has a binomial distribution with the probability of a success being 0.2 and the number of independent trials is 15. The random variable xbar is the mean of a random sample of 100 values of X. Find P(xbar<3.15).

**Statistics/Probability**

The life span of a calculator has a normal distribution with a mean of 60 months and a standard deviation of 5 months. If a calculator is randomly selected, find the probability that the calculator has a life span of. (1) more than 50 months (2) between 4 years and 6 years.

**statistics**

In the old days, we could buy 8 inch floppies for our computers on which to store our favorite programs and data. But, the manufacturing ability was not that good back then and 1% of these 8 inch floppies sold had a bad sector or two on them which made them have less memory ...

**statistics**

30 new babies were born yesterday in the hospital. If the average weight of a new born is 7.5 pounds with a standard deviation of 2.1 pounds, what is the probability of the average weight for these 30 newborns is between 7.2 and 7.6 pounds. Remember, all probabilities are ...

**statistics**

When using the normal approximation to the binomial, what is the standard deviation used in the standardization formula when approximating a binomial distribution with 226 trials and p=0.25? Please submit your answer with 4 decimal places

**statistics**

You have a box of 15 widgets whose average weight for each individual widget is 10 pounds with a standard deviation of 4.0 pounds. Based on this information, what is the standard deviation, taken to 4 decimal places, for the sample average of the weight of the widgets in the box?

**statistics**

When using the normal approximation to the binomial, what is the mean used in the standardization formula when approximating a binomial distribution with 123 trials and p=0.35? Please submit your answer with 2 decimal places

**statistics**

you have a box of 12 widgets whose average weight for each individual widget is 2.6 pounds with a standard deviation of 3.3 pounds. Based on this information, what is the mean, taken to 1 decimal place, for the sample average of the weight of the widgets in the box

**statistics**

Suppose that the ages of students at a particular university average 26 years with a standard deviation of 2.8 years. Consider the sampling distribution of the sample mean age of students in a sample of n = 49. The mean of the sampling distribution is __________

**Statistics/Probability**

The probability the New Year's day is on Saturday is a randomly chosen year is 1/7. 15 years was chosen randomly. Find the probability that, (1) Exactly four of these years have a New Year's day on a Saturday. (2) At least two of these years have New Year's day on a Saturday.

**statistics, probability**

It has been found out that the probability that a child is a male in family is 0.4. In a family of 6 children, what is the probability that; i. exactly 5 are boys ? ii. at least 4 are boys ? iii. all boys

**Statistics**

The life of an electric light bulb is known to be normally distributed with a mean of 2000 hours and a std. of 120 hours. Find the probability that the life of such a bulb would be. (a) greater than 2150 hours (b) within the range of 1850 hours to 2090 hours

**Math (statistics)**

In an examination a candidate is given the four answers to four questions but is not told which answer applies to which question. He is asked to write down each of the four answers next to its appropriate question. b). show that there are 6 ways of getting just two answers in ...

**statistics**

What formula do I use to solve: A sample with a mean of M = 40 and a variance of s2 = 20 has an estimated standard error of 2 points. How many scores are in the sample?

**statistics**

A teacher wants to compare the mean geology scores of two different classes. She is testing the null hypothesis that there is no difference in the population mean scores of the two classes. The difference of the sample means is 51.4. If the standard deviation of the ...

**Math/Statistics**

A group of 10 students have average of GPA of 2.8 with SD of 0.3. Does this group present enough evidence to indicate that the average GPA is less than 3.0? Make your decision at a 5% level of significance.

**Statistics**

A group of 10 students have average of GPA of 2.8 with SD of 0.3. Does this group present enough evidence to indicate that the average GPA is less than 3.0? Make your decision at a 5% level of significance

**statistics**

Twelve different video games showing substance use were observed and the duration times of game play (in seconds) are listed below. The design of the study justifies the assumption that the sample can be treated as a simple random sample. Use the sample data to construct and ...

**statistics**

Could someone let me know if I did this correctly? Source Sum of Squares (degrees of freedom [df]) Mean Square Fobt. Fcrit. Gender 68.15 1.07 68.15/63.685 0.59 1.07,1,2 Marital Status 127.37 3.04 63.685/20.95 0.75 3.04,2,2 Gender * Marital Status (A x B) 41.90 2.28 20.95/9.2 0...

**statistics**

As a marketing promotion a company is going to give the first 200 customers a coupon for a discount when they enter the store. The customer cannot scratch off the coupon until they check out. the company orders 200 coupons and 150 are for 5% off, 30 are for 10% off, 15 are for...

**statistics**

Describe one of the following experiments, which study human subjects, in 450 to 750 words: A pharmaceutical company wants to test a new sleep aid. An educational company is interested in determining whether their new math curriculum will raise standardized test scores. ...

**statistics**

If you are told the mean grade in ECON 2023 is 80 with a standard deviation of 5, what is the probability that if you randomly selected 36 students you would find an average grade of 82 or more? I found the Z-score: 82-80/5 Which gave me .6554 then 1-.6554=.3446 So 34% would ...

**statistics**

Blood type AB is found in only 3% of the population†. If 240 people are chosen at random, find the probability of the following. (Round your answers to four decimal places.) (a) 5 or more will have this blood type (b)between 5 an 10 will have this blood type

**Math**

Statistics show that the sales force of a certain company successfully closed 296 sales out of 800 sales calls. What was their percent success rate?

**Statistics**

If a couple has 4 children and none are from multiple births or twins. With the probability of sons being 50% how many sons would they expect to have?

**Statistics**

The mean score on the first calculus exam was 55%. The standard deviation was 7%. Find the smallest interval about the mean that must contain at least 83% of the scores. heeellllppppp

**statistics**

At the start of December 2001, the retail price of a 25kg bag of cornmeal was $10 in Zambia, while by the end of the month, the price had fallen to $6. The result was that one retailer reported an increase in sales from 3 bags/day to 5 bags/day. Assume that the retailer is ...

**statistics**

in november 2008, apple stock dropped from $105 to $95 per share, and Microsoft dropped from $21 to $20 per share. If you invested a total of $3,570 in these stocks at the end of October and sold them for $3,250 at the end of November, how many shares of each stock did you buy?

**statistics**

help! where do i begin with this problem...in one area, monthly incomes of technology related workers have a standard deviation of $650. It is believed that the standard deviation of monthly incomes of non-technology workers is higher. A sample of 71 non technology workers are...

**statistics**

how much sale tax in due for a payment of 993.91

**statistics**

One of the ways most people relieve stress is to reward themselves with sweets. According to one study in Food Technology, 46 percent admit to overeating sweet foods when stressed. Suppose that the 46 percent figure is correct and that a random sample of 100 people is selected...

**Statistics**

Compute the critical value za/2 that corresponds to a 85% level of confidence.

**Statistics**

An investor has $1400 to invest, and his financial analyst recommends two types of junk bonds. The A bonds have a 6% annual yield with a default rate of 3%. The B bonds have a 9% annual yield with a default rate of 7%. (If the bond defaults, the $1400 is lost.) Which of the ...

**Statistics**

A statistics professor plans classes so carefully that the lengths of her classes are uniformly distributed between 50.0 and 52.0 minutes. Find the probability that a given class period runs between 50.25 and 50.5 minutes.

**Statistics**

Many states are carefully considering steps that would help them collect sales taxes on items purchased through the Internet. How many randomly selected sales transactions must be surveyed to determine the percentage that transpired over the Internet? Assume that we want to be...

**statistics**

A Gallup poll of 1236 adults showed that 12% of the respondents believe that it is bad luck to walk under a ladder. Consider the probability that among 30 randomly selected people from 1236 who were polled, there are at least 2 who have that belief. Given that the subjects ...

**Statistics**

Find the critical value za/2 that corresponds to the given confidence level. 96%

**Statistics**

Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. n=21, x=18, p=0.75

**Statistics**

The distribution of IQ scores is a nonstandard normal distribution with a mean of 100 and a standard deviation of 15. What are the value of the mean and standard deviation after all IQ score have been standardized by converting them to z scores?

**Statistics**

Find the critical values x2L and x2R that correspond to the given confidence level and sample size. 99%: n=23

**statistics**

Assume that a procedure yields a binomial distribution with a trial repeated n times. Use a binomial probabilities table to find the probability of x successes given the probability p of success on a given trial. n=8, x=2, p=0.30

**Statistics**

A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 320 babies were born, and 256 of them were girls. Use the sample data to construct a 99% confidence interval estimate of the percentage of girls born. Based on the results, ...

**statistics**

simple randon sampling uses a sample size n

**Statistics**

An unbiased die is thrown seven times. Find the probability of throwing it at least five six's.

**statistics**

Select which of the following are examples of parameters from these examples. Question options: The probability that a ticket with be a winner is .2 (or a 20% chance) The proportion of winning tickets in the sample of 100 99% of samples will have between 37% and 43% of voters ...

**statistics**

use SPSS to calculate the 90%, 95% and 99% confidence intervals for the mean of the variable weight. Interpret the three confidence intervals in terms of whether there is a significant difference between the mean of the sample and a hypothesized mean of 150.

**statistics**

The inside diameter of metal washers produced by a company are normally distributed with a mean of .5 inches and a standdrd deviation of .01 inches. Of all washers produced .8% of the washers are rejected because they are too small for a bolt used to test them. What is the ...

**statistics**

To find out what people think, the Gallup Poll selected a random sample of 520 women and 506 men. The pollsters showed them a list of personal attributes and asked them to indicate whether each attribute was “generally more true of men or of women”. When asked about ...

**statistics**

2. A researcher measures the heart rate in a population of runners and finds they have an average heart rate of µ = 50, σ = 5. You do not need to show a graph, only computation work. 2A. Based on the average heart rate cited above, what proportion would we expect to have...

**statistics**

construct a 95% confidence interval estimate for the population mean MPG of 2010 family sedans, assuming a normal distribution.

**Statistics (Check Work)**

Can Someone help me with these 2 problems? I am certain I am solving them correctly, but for some reason the computer keeps marking my answers as incorrect. Question 1: Minnesota had the highest turnout rate of any state for the 2012 Presidential election. Political analysts ...

**Statistics**

1. In a study of heart disease in male federal employees, researchers classified 170 volunteer subjects according to their socioeconomic status (SES) and their smoking habits. SES categorized as high and low. Individuals were asked whether they were smokers or non-smoker. Here...

**statistics**

A sample of 40 CDs from a student's collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. Construct a 95% confidence interval for the population standard deviation. (Round your answers to 4 decimal places.)

**statistics**

Facebook reports that the average number of Facebook friends worldwide is 150 with a standard deviation of 90. If you were to take a sample of 25 students, what is the probability that the mean number Facebook friends in the sample will be 165 friends or more?