# Homework Help: Math: Statistics

## Recent Homework Questions About Statistics

**Statistics**

What are some parallels and differences between regression models and time series models? Share some use cases to add to your discussion of the similarities and differences.

*Thursday, March 24, 2016 by Anonymous*

**Statistics**

what is seasonality in a time series and how could it impact modeling a response over time?

*Thursday, March 24, 2016 by Anonymous*

**Statistics**

How do the 3rd grade boys’ weight in Principal Ben’s school compare to the national average (mean weight = 90, sd =15)? Provide the IV, DV, and best method of analysis

*Wednesday, March 23, 2016 by Anonymous*

**statistics**

Among 15 metal parts produced in a machine shop, 4 are defective. If a random sample of five of these metal parts is selected, find a) The probability that this sample will contain at least three defectives. b) The probability that this sample will contain at most two defective.

*Wednesday, March 23, 2016 by akb*

**statistics**

Among 15 metal parts produced in a machine shop, 4 are defective. If a random sample of five of these metal parts is selected, find a) The probability that this sample will contain at least three defectives. b) The probability that this sample will contain at most two defective.

*Wednesday, March 23, 2016 by akb*

**Statistics**

The home states of a certain group of people are distributed as follows: 54 percent are from MISSOURI, 27 percent are from KANSAS, and 19 percent are from IOWA. (No one in the group had a home state other than one of these three.) (Note: Your answer to the question below ...

*Tuesday, March 22, 2016 by Mal*

**Probability and 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=22, x=18, p=0.85, q=.15

*Tuesday, March 22, 2016 by Holly*

**statistics of business**

A telephone company’s goal is to have no more than six monthly line failures on any 100 kilometres of line. The company currently experiences an average of three monthly line failures per 50 kilometres of line. Let x denote the number of monthly line failures per 100 ...

*Monday, March 21, 2016 by Yogeswar*

**STATISTICS**

A math teacher observes that on the average 3 students came to their 8-9AM class late. The probability 5 students will be late in their 8-9AM class is ???

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A math teacher observes that on the average 3 students came to their 8-9AM class late. The probability 5 students will be late in their 8-9AM class is ????

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A math teacher observes that on the average 3 students came to their 8-9AM class late. The probability 5 students will be late in their 8-9AM class is ???

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

The probability that a certain production process will produce a defective part is 0.20. If a box contains 12 parts, the probability that there will be 6 or 7 defective parts is ??

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

The probability that a certain production process will produce a defective part is 0.20. If a box contains 12 parts, the probability that it will contain 6 defective parts is?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A coin is tossed 4 times, the probability that all heads and all tails will appear is??

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A coin is tossed 3 times and let X be the number of heads appearing. The probability that 1 head will appear iS?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

On the average, 6 people per hour use an express teller machine situated inside a commercial complex. What is the probability that, from 3:00-4:00pm on Friday, at most 4 people will use the machine?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

On the average, 7 people per hour use an express teller machine situated inside a commercial complex. What is the probability that, from 3:00-4:00pm on Friday, exactly 7 people will use the teller machine?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A store owner complains that, on the average, 3 bottles per case of a certain brand of softdrink are underfilled. Assuming this is correct, find the probability that a randomly chosen case of this drink will contain at least 4 underfilled bottles.

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

Suppose that airplane engines operate independently in flight and fail with probability 1/5. Assuming that a plane makes a safe flight if at least one-half of its engines run, what is the probability that 4-engine plane has a successful flight?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

In a certain city district, the need for money to buy drugs is given as the reason for 65% of all thefts. What is the probability that exactly 2 of the next 4 theft cases reported in this district resulted from the need for money to buy drugs?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A multiple-choice quiz has 15 questions, each with 4 possible answers of which only 1 is the correct answer. What is the probability that a student gets at least 1 correct answer?

*Monday, March 21, 2016 by NARUTO*

**STATISTICS**

A multiple-choice quiz has 15 questions, each with 4 possible answers of which only 1 is the correct answer. What is the probability that a student gets exactly 8 correct answers?

*Monday, March 21, 2016 by NARUTO*

**Applied statistics**

A fireworks show is designed so that the time between fireworks is between one and five seconds, and follows a uniform distribution. a. Find the average time between fireworks. b. Find probability that the time between fireworks is greater than four seconds.

*Sunday, March 20, 2016 by Nandini*

**chemistry/statistics**

replicate water samples were analyzed for water hardness with the following results : 102.2 , 102 .8 ,103.1, 102.3 of calcium trioxocarbonate . calculate the standard deviation of the mean and the coefficient of variation

*Saturday, March 19, 2016 by austin*

**statistics**

I don't know what scale to use in plotting the graph of this table; T[k]. D(g/ml) 263. 13.62 273. 13.60 283. 13.57 303. 13.55 313. 13.52 323. 13.42

*Saturday, March 19, 2016 by austin*

**Statistics**

Suppose that a researcher wants to estimate a proportion P to within .02 with 95% probability. What is the minimum sample size required?

*Saturday, March 19, 2016 by Alfonzo*

**statistics**

Suppose that you are in a class of 28 students and it is assumed that approximately 8% of the population is left-handed. (Give your answers correct to three decimal place. Compute the probability that exactly five students are left-handed

*Friday, March 18, 2016 by Kyra*

**statistics**

Suppose babies born in a large Hospital have a mean weight of 4088 in a variance of 5569. if 128 babies are sample that a random from the hospital what is the probability that the mean weight of the sample babies would differ from the population mean by less than 41 grams ...

*Thursday, March 17, 2016 by Marcus*

**statistics**

In a hospital 6 deliveries have been occurred. The probability that the baby is female equal 0.48 a. Find the probability distribution of the variable representing the number of female babies.

*Thursday, March 17, 2016 by Nada*

**statistics**

A sign on the gas pumps of a chain of gasoline stations encourages customers to have their oil checked, claiming that one out of four cards need to have oil added. If this is true, what is the probability of the following events? a. One out of the next four cars needs oil. b. ...

*Thursday, March 17, 2016 by April*

**statistics**

From experience, the manager of a bookstore knows that 40% of the people browsing in his store will make a purchase. If on a certain day, 360 people come into the store a) what is the probability that exactly 144 of them make a purchase? b) what is the probability that at more...

*Wednesday, March 16, 2016 by McKinsley*

**Math (statistics)**

The probability of obtaining heads on a biased coin is 0.4. The coin is tossed 600 times. a. i. Write down the mean number of heads (240) ii. Find the standard deviation of the number of heads (12) b. Find the probability that the number of heads obtained is less than one ...

*Wednesday, March 16, 2016 by Myra*

**statistics**

Find the following: P(z > 2.43)

*Wednesday, March 16, 2016 by Ray*

**Statistics**

a study shows that 16% of household appliances break during any given year. If a person has 4 household appliances, what is the probability that exactly 1 of them will break next year? I just need a formula and I can get it from there.

*Saturday, March 12, 2016 by T*

**Statistics**

In a prior sample of U.S. adults, the Center for Disease Control (CDC), found that 10% of the people in this sample had pinworm but the margin of error for the population estimate was too large. They want an estimate that is in error by no more than 1.5 percentage points at ...

*Friday, March 11, 2016 by Sara*

**Statistics**

Suppose you draw a card from a deck (with replacement) 10 times in a row. What is the probability that you get exactly 3 hearts? Round your answer to 3 decimal places.

*Friday, March 11, 2016 by Sara*

**Statistics**

In testing a new drug, researchers found that 20% of all patients using it will have a mild side effect. A random sample of 25 patients using the drug is selected. Find the mean and standard deviation of patients having a mild side effect. Mean = np = 25(.2) = 5 Ok Standard ...

*Friday, March 11, 2016 by Ray*

**statistics**

Case Study Chapter 6 and 7 FOR FULL CREDIT SHOW EQUATIONS USED AND WORK. ELEVATOR CAPACITY: Suppose an elevator has a maximum capacity of 16 passengers with a total weight of 2500 lbs. The mean weight of females is less than the mean weight of males so we will only look at ...

*Monday, March 7, 2016 by Chris*

**Statistics**

A bolt manufacturer is using a hypothesis test with α = 0.01 to see if the diameter of their 0.75 cm diameter bolts are being manufactured properly. The goal is to have the average bolt diameter be 0.75 ± 0.0075 cms.

*Monday, March 7, 2016 by Sarah*

**Statistics Please help me :(**

I have no idea where to even start. Suppose heights of men are normally distributed with a mean 69.0 inches and standard deviation 2.8 inches. How many of a group of 1000 men would you expect to be between 70 and 72 inches tall? Round to the nearest whole number. Suppose ...

*Monday, March 7, 2016 by Anonymous*

**Statistics**

Suppose heights of men are normally distributed with a mean 69.0 inches and standard deviation 2.8 inches. What percent of men are over 6 feet tall? Round to the nearest tenth of a percent. I understanf finding the z score, but I'm not sure how to find the percent.

*Sunday, March 6, 2016 by Anonymous*

**Statistics**

Suppose a baseball pitcher throws fastballs 80 % of the time and curveballs 20 % of the time. Suppose a batter hits a home run on 8 % of all fastball pitches, and on 5 % of all curveball pitches. What is the probability that this batter will hit a home run on this pitcher's ...

*Sunday, March 6, 2016 by Nicole*

**Statistics**

Hi, I was studying for the math HL exam but I was stuck on Problem 6. I attached it as an image. imgur. com/a/XY874 There's a space because Jiskha does not let me post links.

*Sunday, March 6, 2016 by cory*

**Statistics**

Drug clinical trials are analyzed using hypothesis testing methods. As we’ve discussed, the null hypothesis in the effective stage of such trials is that the drug being tested is ineffective. The alternative, of course, is that the drug is effective. Explain why such tests ...

*Sunday, March 6, 2016 by Sarah*

**Statistics**

Recall that the power (1 – β) of a hypothesis test is the probability that we will reject the null hypothesis given that it is false; that is, the probability that we will correctly reject the null hypothesis. All other things being equal, which of the following changes...

*Sunday, March 6, 2016 by Sarah*

**Statistics**

he level of nitrogen oxides (NOX) in the exhaust of a particular car model varies with mean 0.7 grams per mile and standard deviation 0.19 grams per mile . (a) What sample size is needed so that the standard deviation of the sampling distribution is 0.01 grams per mile ?

*Saturday, March 5, 2016 by zoolo*

**Statistics**

TRUE or FALSE: The p-value of a hypothesis test is the probability that the null hypothesisis true given the sample statistic obtained.

*Saturday, March 5, 2016 by Sara*

**Statistics**

Imagine you're a researcher and you need to perform a one-sided test of an alternative hypothesis. You decide to conduct a significance test at the .05 level. Which of the following ranges of z-scores would make the test statistic significant at .05 (one-tail) but not at .01? ...

*Friday, March 4, 2016 by Jim*

**statistics**

Find the number of different selections of 4 letters from the 9 letters of the word HAPPINESS which contain no P's and either one or two S's.

*Friday, March 4, 2016 by Zeest*

**statistics**

if 3 couples sit in a row of chairs what is the probability that each couple sits together? what is the probability all the women sit together and the men may or may not be in the group? what is the probability that the women sit together and the men sit together?

*Thursday, March 3, 2016 by brittaney*

**statistics**

after rolling 5 dice , what is the probability that all 5 of the values are different? 720/7776

*Thursday, March 3, 2016 by brittaney*

**statistics**

a math class has 50 students , of these 22 students are math majors and 18 students are male. Of the math majors 16 are female. Find the probability that a randomly selected student is male or a math major . my answer 22/50 and 18/50 = 396/50= 7.29

*Thursday, March 3, 2016 by brittaney*

**statistics**

If a random password is 3 letters(a-z) and 1 number (0-9) what is the possibility that the password will have 2 of the same letters? 26x26x26=17576

*Thursday, March 3, 2016 by brittaney*

**Statistics**

If four coins are flipped at once, find the probability that there will be at least 2 heads. Round your answer to 3 decimal places.

*Wednesday, March 2, 2016 by Hunter*

**Statistics**

Two high school students took equivalent language tests, one in German and one in French. The student taking the German test, for which the mean was 66 and the standard deviation was 8, scored an 82, while the student taking the French test, for which the mean was 27 and the ...

*Wednesday, March 2, 2016 by Anonymous*

**Statistics**

A particular fruit's weights are normally distributed, with a mean of 764 grams and a standard deviation of 33 grams. The heaviest 15% of fruits weigh more than how many grams? Give your answer to the nearest gram.

*Monday, February 29, 2016 by Bailey*

**Statistics**

A random variable x has the following probability distribution: x f(x) 0 0.08 1 0.17 2 0.45 3 0.25 4 0.05

*Sunday, February 28, 2016 by Donzella*

**research statistics**

Forty-nine items are randomly selected from a population of 500 items. The sample mean is 40 and the sample standard deviation 9. Develop a 99% confidence interval for the population mean. (Round your answers to 3 decimal places.)

*Saturday, February 27, 2016 by myke*

**Statistics**

In a shipment of 21 parts, four of the parts are defective. If three parts are selected at random without replacement, find the probability that : a.) All three parts selected are defective. 4/21*3/20*2/19=.003 b.) None of the tree parts selected are defective. 3/17*2/16*1/15...

*Friday, February 26, 2016 by Grace*

**statistics please help!**

Assume an office has two telephones (A and B) with separate lines and different telephone numbers. The probability that telephone A rings when the office is closed is .30. The probability that telephone B rings when the office is closed is .20 What is the probability that A ...

*Thursday, February 25, 2016 by Alondra*

**statistics please help!**

Assume an office has two telephones (A and B) with separate lines and different telephone numbers. The probability that telephone A rings when the office is closed is .30. The probability that telephone B rings when the office is closed is .20. What is the probability that ...

*Thursday, February 25, 2016 by Alondra*

**statistics please help!**

Assume an office has two telephones (A and B) with separate lines and different telephone numbers. The probability that telephone A rings when the office is closed is .30. The probability that telephone B rings when the office is closed is .20 What is the probability that ...

*Thursday, February 25, 2016 by Alondra*

**statistics please help!**

Assume an office has two telephones (A and B) with separate lines and different telephone numbers. The probability that telephone A rings when the office is closed is .30. The probability that telephone B rings when the office is closed is .20. What is the probability that ...

*Thursday, February 25, 2016 by Alondra*

**Statistics for the Behavioral Sciences**

Complete an independent project, collect data from your observation experiment and perform a one-way, between-subjects ANOVA on the data using the definitional formula.Include the following: 1. description of research project that includes the operational definition for the ...

*Thursday, February 25, 2016 by Pamela*

**statistics please help!**

If 3 cards are drawn with replacement from a shuffled deck, what is the probability that at least one of them will be a heart

*Thursday, February 25, 2016 by Denise*

**statistics please help!**

If 3 cards are drawn with replacement from a shuffled deck, what is the probability that none of the 3 will be hearts?

*Thursday, February 25, 2016 by Denise*

**statistics please help!**

If 3 cards are drawn with replacement from a shuffled deck, what is the probability that all 3 will be hearts?

*Thursday, February 25, 2016 by Denise*

**statistics**

Identify the level of measurement of the data and explain what is wrong with the given calculation. In a set of data, movie ratings are represented as 100 for 1 star, 200 for 2 stars, and 300 stars for 3 stars. The average (mean) of the 527 movie ratings is 231.2. I got ...

*Thursday, February 25, 2016 by Anonymous*

**Statistics**

The mean grade in this class last semester was 78.3, and the variance was 49 . The distribution of grades was unimodal and symmetrical. Using this information determine the probability that “Joe”, a random student you know nothing about, other than the fact that they are ...

*Thursday, February 25, 2016 by Francisco*

**statistics**

If p(A)=.50, p(B)=.60, and p(A and B)=.30, Are A and B mutually exclusive events? and independent events?

*Thursday, February 25, 2016 by Nelly*

**statistics**

if a die is tossed four times what is the probability of getting at least one six

*Thursday, February 25, 2016 by Nelly*

**statistics**

if a die is tossed four times what is the probability of getting anything but a five on every toss

*Thursday, February 25, 2016 by Nelly*

**statistics**

if a die is tossed four times what is the probability of getting three odd numbers

*Thursday, February 25, 2016 by Nelly*

**statistics**

if a die is tossed four times what is the probability of getting one six

*Thursday, February 25, 2016 by Nelly*

**statistics**

5 students go to school one of which is known to be late; in fact he is late 22% of the time. What is the probability that he will not be late for school.

*Wednesday, February 24, 2016 by Sam*

**statistics**

5 cards are drawn out of a regular deck without replacement; you win if you get at least one red card. What is the probability of getting at least one red card?

*Wednesday, February 24, 2016 by Shawn*

**Statistics**

To win one version of the New York State lottery, one must correctly select 5 numbers from 49 numbers. How many different selections are possible if: ~ The order in which the selection is made does not matter? ~ The order of selection does matter?

*Wednesday, February 24, 2016 by Ana*

**statistics**

The second moment about mean oftwo distributions are 13.76 and 63.0 while the fourth moment about the men are 528.06 and 9500 respectively which of distribution is 1 leptokuric [2] mesokuric [3] platykurtic

*Monday, February 22, 2016 by shumaila*

**statistics**

Minutes 126.53 127.27 130 130.35 130.4 130.58 130.87 131.18 131.98 132.55 133.28 133.42 133.43 133.55 133.65 134 134.37 134.62 134.73 135 135.95 136.12 136.17 136.23 136.28 137.7 137.83 137.93 138.18 138.25 138.43 138.67 139.13 139.72 140.25 140.38 140.4 140.42 140.5 141.27 ...

*Sunday, February 21, 2016 by hana*

**statistics**

state whether the quantity described is a parameter or a statistic and give the correct notation. Correlation between height and weight for players on the 2010 Brazil World Cup team, using data from all 23 players on the roster. thanks

*Sunday, February 21, 2016 by hana*

**statistics**

Minutes 126.53 127.27 130 130.35 130.4 130.58 130.87 131.18 131.98 132.55 133.28 133.42 133.43 133.55 133.65 134 134.37 134.62 134.73 135 135.95 136.12 136.17 136.23 136.28 137.7 137.83 137.93 138.18 138.25 138.43 138.67 139.13 139.72 140.25 140.38 140.4 140.42 140.5 141.27 ...

*Sunday, February 21, 2016 by vicke*

**statistics**

Minutes 126.53 127.27 130 130.35 130.4 130.58 130.87 131.18 131.98 132.55 133.28 133.42 133.43 133.55 133.65 134 134.37 134.62 134.73 135 135.95 136.12 136.17 136.23 136.28 137.7 137.83 137.93 138.18 138.25 138.43 138.67 139.13 139.72 140.25 140.38 140.4 140.42 140.5 141.27 ...

*Saturday, February 20, 2016 by Anonymous*

**Statistic**

Your search for statistics test questions a professor is trying to convince her colleagues that peer tutoring works. she compares the results of students in two classes one with and one without the peer tutoring. for the non-tutored group the mean score fore for 35'studentsnis...

*Friday, February 19, 2016 by Dhelp*

**statistics**

Minutes 126.53 127.27 130 130.35 130.4 130.58 130.87 131.18 131.98 132.55 133.28 133.42 133.43 133.55 133.65 134 134.37 134.62 134.73 135 135.95 136.12 136.17 136.23 136.28 137.7 137.83 137.93 138.18 138.25 138.43 138.67 139.13 139.72 140.25 140.38 140.4 140.42 140.5 141.27 ...

*Friday, February 19, 2016 by Anonymous*

**statistics**

Suppose the temperature of a cup of coffee is normally distributed with a mean of 142 degress F. If a cup of coffee has a z score of 1.5, which of the following is true?

*Friday, February 19, 2016 by PLZ HELP*

**Statistics**

The distribution of student loan amounts for students is normally distributed ranging from zero to $100,000. Use your knowledge of the Empirical Rule to approximate the standard deviation of the dataset? A) approximately $21,000 B) approximately $12,500 C) approximately $19,...

*Friday, February 19, 2016 by Anonymous*

**Statistics**

If, for a given sample size, 10% of all possible confidence intervals do not contain the unknown population parameter value, what is your confidence level?

*Friday, February 19, 2016 by Anonymous*

**Statistics**

Country Insurance wants to estimate the cost of damage to cars due to accidents. The population standard deviation of the cost is assumed at $200. They want to estimate the mean cost using a 95% confidence interval with a maximum margin of error of $10. What is the minimum ...

*Friday, February 19, 2016 by Anonymous*

**Statistics**

ATM transaction times are normally distributed with a mean of 150 seconds and a standard deviation of 45 seconds. What is the probability a person takes less than 60 seconds to complete their transaction?

*Friday, February 19, 2016 by Anonymous*

**statistics**

Two cards selected from standard deck of 52 cards. The first is replaced before second card selected. Find the probability of selecting a diamond and then a king

*Thursday, February 18, 2016 by tim*

**Statistics**

The following is a histogram (right skewed) of the first ten terms of a geometric distribution with p = .4. The mean of this distribution is 2.5 and the standard deviation is approximately 1.93. What's the shape of the distribution of sample means for simple random samples of ...

*Thursday, February 18, 2016 by Jim*

**Statistics**

What is the difference between the population distribution, the distribution of the same, and the sampling distribution and what are the formulas to get the normal distribution of each?

*Tuesday, February 16, 2016 by Sara*

**statistics**

FBM 124 class consists of 10 male and 12 female students. Two students were chosen to represent the university to an international forum. Compute the probability of choosing (a) two female students (b) no more than 1 male student c)same genders students

*Tuesday, February 16, 2016 by Anonymous*

**Statistics**

A volunteer ambulance service handles 0 to 5 service calls on any given day. The probability distribution for the number of service calls is as follows: one column has number of service calls (X) those numbers are 0 1 2 3 4 5. The next column Probability P (X) those numbers ...

*Saturday, February 13, 2016 by Karen*

**Statistics**

A sample of size 16 is taken from a normally distributed population with a mean of 12 and a standard deviation of 3. The probability that the sample mean is equal to 12 is a. 1 b. 0.5 c.-0.5 d.0 please explain

*Friday, February 12, 2016 by Sara*

**statistics**

Scores: 5,2,4,2 ΣX-2 Σ(X-2) Σ(X-2)^2 can you show me a better idea how to solve this thanks

*Thursday, February 11, 2016 by bob*

**Statistics**

When a new machine is functioning properly, only 2% of the items produced are defective. If 5 parts are randomly selected from this production process, what is the probability that at most 1 defective item is in the sample?

*Wednesday, February 10, 2016 by lonestar college*

**Statistics**

2.5 Points 30% of the fifth grade students in a large school district read below grade level. The distribution of sample proportions of samples of 100 students from this population is normal with a mean of 0.30 and a standard deviation of 0.045. Suppose that you select a ...

*Wednesday, February 10, 2016 by Amy*

**statistics**

A play contains 15 speaking roles, 10 of them female and 5 male. If the director can choose among 16 female actors and 9 male actors to fill the roles, how many different casts are possible? (NOTE: A cast includes BOTH the actor AND the role that they play.) I'm just confused ...

*Monday, February 8, 2016 by McKinsley*

**Statistics**

We are managing a large soy bean farm. To estimate our revenues for the coming year, we need to estimate our crop yield. Soy bean yields are measured by pods/plant. We are planning for a yield of 40 pods/plant. a. We take a random sample of 64 soy bean plants and get a sample ...

*Monday, February 8, 2016 by Sara*