# random

4,609 results, page 23

### math

A box contains 8 blue balls and 2 red balls. Three balls are selected from the box at random without replacement. Find the probability that two balls are blue and one ball is red.

### math

A candidate believes that 2/3 of the registered voters in his district will vote for him in the next election. If two registered voters are independently selected at random, find the probability that neither will vote for him in the next election.

### Statistics

among customers- 70% buy popcorn, 40% buy ice cream, and 25% by both. Suppose you pick one customer at random. Find the probability the customer buys popcorn or ice cream.

### stats.

The mean number of bumped airline passengers per day s 1.35 and the standard deviation is 0.25. For a random selection of a group of 40 days, what is the probability that the mean number of bumped passengers for the 40 days will be between 1.25 and 1.50?

### math

John has 2 coins, one fair and the other unbalanced so that the probability of its coming up heads is 2/3. He picks one of the coins at random, tosses it, and it comes up heads. What is the probability that he picked the unbalanced coin?

### elem math core

A bag contains one each of red, blue, green, yellow and white marbles. Give the sample space for the following experiments. A) one marble is drawn at random B) one marble is drawn, but not replaced,and then a second marble is drawn.

### statistics

The average teenager spends 7.5 hours per week playing computer and video games. In a random sample of 110 teenagers, what is the probability that their mean time for playing games is more than 8 hours per week?

### Statistics

(a) If 10 auto insurance claims are taken at random, use the binomial distribution to determine the probability that: (i) at least 6 claims are fraudulent (ii) at most 3 claims are fraudulent (iii) anywhere between 5 and 8 (inclusive) claims are fraudulent (iv) at least 1 ...

### statistics

suppose 25% of the urban population is 18 years old or younger. five residents of that city are selected at random find the probability that at least two of the selected five persons are 18 years old or younger. please help me with this question !!!

### Statistics

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

### MATH

NOT INDEPENDENT A box contains four white, three red, and two black marbles. Three marbles are chosen at random. a. What is the probability that all three are the same color? b. What is the probability that all three are different colors?

### probability

An employer wishes to hire three people from a group of 15 applicants 8 men and 7 women, all of which are equally qualified to fill the position . if the three are selected at a random. what is the probability, a) All will be men? b) at least one will be a women?

### stats

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

### probability

Random variables X and Y are distributed according to the joint PDF fX,Y(x,y) = {ax,0,if 1≤x≤2 and 0≤y≤x,otherwise. 1 Find the constant a. a= 2 Determine the marginal PDF fY(y). (Your answer can be either numerical or algebraic functions of y). For 0&#...

### Probability

Random variables X and Y are distributed according to the joint PDF fX,Y(x,y) = {ax,0,if 1≤x≤2 and 0≤y≤x,otherwise.} 1. Find the constant a. 2. Determine the marginal PDF fY(y). (Your answer can be either numerical or algebraic functions of y). For 0&#...

### English

This is a homework question, but one I have been curious about since I could pick up a book. Why are there brackets around random words in a quote? For example on book reviews there are brackets around one or a few words and I can't understand why.

### STATISTICS HELP PLEASE!

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

### statistics

Help me! Population of heights of college students is approximately normally distributed with a mean of 64.37 inches and standard deviation of 6.26 inches A random sample of 74 heights is obtained. Find the mean and standard error of the x bar distribution 2. Find P(xbar > ...

### statistics

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

### Statistics

In a department store there are 120 customers, 90 of whom will buy at least 1 item. If 5 customers are selected at random, one by one, find the probability that all will buy at least 1 item.

### intro to statisics

78% of US homes have a telephone answering device. In a random sample of 250 homes, what is the probability that fewer than 50 do not have a telephone answering device. Courtney, 2nd yr college

### probability

Four balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white

### Math

Five balls are selected at random without replacement from an urn containing three white balls and five blue balls. Find the probability that two or three of the balls are white.

### Statistics

A random sample of size 36 is to be selected from a population that has a mean μ = 50 and a standard deviation σ of 10. - - Find the mean of this sampling distribution. - Find the standard error of this sampling distribution.

### statistics

of the physics graduates of a university, 35% received a starting salary of \$50,000 or more. If 5 of the graduates are selected at random, find the probability that all had a starting salary of \$50,000 or more.

### statistics

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

### Is this right?? Stats....

Classify the following as discrete or continuous random variables. (A) The time it takes to run a marathon (B) The number of fractions between 1 and 2 (C) A pair of dice is rolled, and the sum to appear on the dice is recorded (D) The length of a broad jump I got: (A) ...

### math

A random group of seniors was selected from a university and asked about their plans for the following year. The school advising office claims that 60% of the students plan to work, 30% of the students plan to continue in school, and 10% of the students plan to take some time ...

### Statistics

If 67% of cars have automatic tranny's & 8 cars are selected at random what is the probability that fewer than 4 have an automatic tranny

### statistics

Suppose we want to estimate the average number of purchases in a given hour in a local convenience store. Using this example describe in your own words how you would go about determining this average through: A.) Drawing a random sample: Drawing a random sample would be the ...

### Stats

Do more than 50% of US adults get enough sleep? According to the Gallup organization's December 2004 Lifestyle Poll, 55% of US adults said that they get enough sleep. The poll was based on a random sample of 1003 adults. Test an appropriate hypothesis and state your conclusion...

### Statistics

Do more than 50% of US adults get enough sleep? According to the Gallup organization's December 2004 Lifestyle Poll, 55% of US adults said that they get enough sleep. The poll was based on a random sample of 1003 adults. Test an appropriate hypothesis and state your conclusion...

### UMD

A new car that is a gas- and electric-powered hybrid has recently hit the market. The distance traveled on one gallon of fuel follows an exponential distributed with a mean of 63 miles. One car is selected at random and is driven on one gallon of gas. What is the probability

### statistics

Let x denote the time taken to run a road race. Suppose x is approximately normally distributed with a mean of 190 minutes and a standard deviation of 21 minutes. If one runner is selected at random, what is the probability that this runner will complete this road race in 225 ...

### Statiatics

Need help please. Determine whether each experiment is a binomial experiment or can be reduced to a binomial experiment. If so, describe a trial, determine the random variable, and state n, p and q. a) You roll a die 15 times and find the sum of all the rolls. Just need this ...

### physics

A hiker makes four straight-line walks A 31 km at 299 degrees B 32 km at 210 degrees C 29 km at 59 degrees D 22 km at 150 degrees in random directions and lengths starting at position (41 km, 41 km). Which vector will return the hiker to the starting point? All angles are ...

### stats of biologists

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

### Algebra

1. A bag contains 9 tiles numbered 1 to 9. p (4) = 1/9. What type of probability is illustrated and why? 2. You toss a coin 15 times. p(heads) 2/5= 3. A number cube is rolled 150 times. The number 3 comes up 43 times. What is the experimental probability of rolling a 3? What ...

### Probability

Erin's CD changer holds 6 compact disks. Justin uses the random function on to play all the songs randomly. If each of the disks on the changer holds 10 songs, what is the probability has favorite song will be first? If I am getting the hang of this, it's 1/2160 Please help.

### statistics

need help on this hw question Scuba-diving trips The mailing list of an agency that markets scuba-diving trips to the Florida Keys contains 60% males and 40% females. The agency calls 30 people chosen at random from its list. What is the probability that 20 of the 30 are men?

### statistics

the quality control inspector of a production plant will reject a batch of syringes it two or more defective syringes are found in a random sample of ten syringes taken from the batch. suppose the batch contains 2% defective syringes. What is the probability that the batch ...

### math

A lottery game has balls numbered 1 through 15. If a ball is selected at random, what is the probability of selecting a ball showing an even number or the number 12? I thought the answer would be 7 even numbers and 1 for the 12 which would be 8/15 is not an option for the ...

### statistics

The weight of a small Starbucks coffee is a normally distributed random variable with a mean of 410 grams and a standard deviation of 10 grams. Find the weight that corresponds to each eventa. A.Highest 30 percent b. Middle 70 percent to c. Highest 90 percent d. Lowest 20 percent

### math

an insurance company reported that 55% of all automobile damage claims were made by people under age 25. If six automobile damage claims were selected at random, determine the probility that exactly four of them were made by someone under ager 25.

### math probability

A box has ten dollars, one is five dollar and four of one dollars. If two bills are chosen at random without replacement, find probability of getting A) amount of valued fifteen dollars B) amount of twelven dollars... is it 4 from 19-15 for A and 7 from 19-12= 7?

### Math

Assume that there are 7 different issues of Newsweek, 8 different issues of Time, and 4 different issues of Sports Illustrated, including the December 1st issue, on the rack. You choose 4 of them at random. What is the probability that you choose at least 1 of the Time magazines?

### csn

In a box there are four prizes that are worth \$30, three prizes worth \$300, and one prize worth \$1000. A player will reach into the box and draw one of the prizes at random. What is the fair price for this game?

### Chemistry

Adding water to some chemicals can be dangerous because large amounts of heat are liberated. Which of the following does NOT liberate heat when water is added to it? KNO3 (the answer) NaOH Na CaO H2SO4 I guessed Na simply because it's the only one that's an element, but this ...

### mayh

Four players are playing a game involving choosing positions on a grid of size 3×8. Each player chooses a random position on the grid, then all players reveal their choices and a token is placed on each of the positions. The probability that the tokens form the vertices of a ...

### math

Four players are playing a game involving choosing positions on a grid of size 3×8. Each player chooses a random position on the grid, then all players reveal their choices and a token is placed on each of the positions. The probability that the tokens form the vertices of a ...

### Math Help

Four players are playing a game involving choosing positions on a grid of size 3×8. Each player chooses a random position on the grid, then all players reveal their choices and a token is placed on each of the positions. The probability that the tokens form the vertices of a ...

### statistics

Five males with a particular genetic disorder have one child each. the random variable x is the number of children among the five who inherit the genetic disorder. Determine whether the table describes a probability distribution. If it does, find the mean and standard ...

### statistics

among the exames in the examination 30%, 35% & 45% failed in statistics, in maths, & in atleast one of the subjects respectively. one student is selected at random. find the probability that: (a)he has failed in maths, (b)he passed in statistiics if it is known that he has ...

### probability

among the exames in the examination 30%, 35% & 45% failed in statistics, in maths, & in atleast one of the subjects respectively. one student is selected at random. find the probability that: (a)he has failed in maths, (b)he passed in statistiics if it is known that he has ...

### Math

Theresa's company just bought 18 new computers. She was told that there would be a random drawing to see which employees got one of the new computers. If Theresa has 46 coworkers, what is the probability that she will get one of the new computers?

### math

A random digit dialing phone survey asked, how many of the last ten traffic lights you drove through were red. Of 880 respondents, 171 admitted at least one light had been red. What is likely direction of the bias: More or fewer than 171 really ran a red light? Why?

### math

1. A teacher has 10 boys and 12 girls in her grade school class. In how many ways can she select 8 of the children to be in a play if she must select 5 boys and 3 girls. 2. The manager of the various displays in the Acme Fine Clothing Emporium has a window which will hold 4 ...

### 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 ...

### Statistics

Hello Can you help me It is reported that 72% of working women use computers at work , choose 4 working wonen at random . Find the probability that : A : all 4 use a computer at their work B : at least one does not use a computer at work Please help me 😞

### Maths

The probability a pupil takes a bus to school is 0.3. If a sample of 10 pupils are chosen at random. Using binomial distribution. Find the probability that a) exactly four pupils travel by bus. b) more than six pupils travel by bus.

### Math

A class is made up of 10 boys and 2 girls. Half of the boys wear glasses. A student is selected at random from the class. What is the probability that the student is a boy with glasses? My Question is, I don't know how to do Probability.

### math

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

### statistics

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

### statistics

A sample of 36 females is taken. What is the probability that the mean height of these women is shorter than 64 inches if we know the height for all American females is N(63,3^2)? What is the probability that a random woman is shorter than 64 inches?

### Math-Probability

An urn contains four red balls and three white balls. A sample of 2 balls is selected at random from the urn. What is the probability that at least one of the balls is red?

### statistics

A simple random sample of 40 items resulted in a sample mean of 25. The population standard deviation is 5. a. What is the standard error of the mean (to 2 decimals)? b. At 95% confidence, what is the margin of error (to 2 decimals)?

### Statistics

A school is running a raffle. There are 100 tickets, of which 3 are winners. You can assume that tickets are sold by drawing at random without replacement from the available tickets. Teacher X buys 10 raffle tickets, and so does Teacher Y. Find the chance that one of those two...

### stats

The mean of nonresidential buildings is 30 years and the standard deviation of the ages of the buildings is 5 years. Determine the probability that a random sample of a group of 50 nonresidential buildings will have a mean age of less than 27.5 years.

### statistics

The mean of nonresidential buildings is 30 years and the standard deviation of the ages of the buildings is 5 years. Determine the probability that a random sample of a group of 50 nonresidential buildings will have a mean age of less than 27.5 years.

### Statistics

Suppose you and a friend each take different random samples of data pairs (x,y) from the same population. Assume the samples are the same size. Based on your samples, you compute r = 0.83. Based on her sample your friend computes 0.79. Is your friend’s value for r wrong? ...

### Math

A box of jelly bears contains 52 jelly bears which 19 are white, 10 are brown, 7 are pink, 3 are purple, 5 are yellow, 2 are orange, and 6 are green. In how many ways can you select 9 pieces of candy at random from the box without replacement if 3 white jelly bears are selected?

### Statistics

Suppose you and a friend each take different random samples of data pairs (x,y) from the same population. Assume the samples are the same size. Based on your samples, you compute r = 0.83. Based on her sample your friend computes 0.79. Is your friend’s value for r wrong? ...

### Stats

What is the probability that a simple random sample of 56 special orders will provide an estimate of the population proportion of special orders specifying the color black that is within plus or minus .05 of the actual population proportion,assuming p = .36? In other words, ...

### statistics

In a random sample of 50 babies 4 to 7 month old the average number of hours they slept per day turned out to be 14.2 hours with a standard deviation of 1.6 hours find and interpret a 90% confidence interval for the mean number of hours slept by babies at this age

### statistics

In a random sample of 50 babies 4 to 7 month old the average number of hours they slept per day turned out to be 14.2 hours with a standard deviation of 1.6 hours find and interpret a 90% confidence interval for the mean number of hours slept by babies at this age

### Stats

A car rental agency currently has 43 cars available, 27 of which have a GPS navigation system. Two cars are selected at random from these 43 cars. Find the probability that both of these cars have GPS navigation systems. Round to four decimal places.

### Statistics

There are 100 questions from a SAT test, and they are all multiple choice with possible answers of a,b,c,d,e for each question only one answer is correct. Find the mean number of correct answers for those who make random guesses for all 100 questions?

### Math

You want to conduct a survey to find out what sport the students at your school prefer to play. a) You interview 20 boys playing football at lunch. Is this a random sample? explain b) The survey question you ask is, ''What is your favorite sport to play?'' Is this question ...

### statistics

(1) The director of a health club conducted a survey and found that 23% of members used only the pool for workouts. Based on this information, what is the probability that for a random sample of 10 members, 4 used only the pool for workouts? Round your answer to four decimal ...

### Math

The table shows the color preference of 50 shoppers at the mal. What is te probability that one shopper, selected at random from the 50 surveyed, preferred the color red or blue? Color preferences color)Number of shoppers) Red)7 yellow)3 blue)13 green)15 orange)12 7/50. MY ...

### Statistics

In a certain city, there are 10,000 persons age 18 to 24. A simple random sample of 500 such persons is drawn, of whom 200 turn out to be currently enrolled in college. Find a 90% con¯dence interval for the percentage of persons age 18 to 24 in the city who are attending ...

### Statistics

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

### Lincoln College Of New En

it has been found that 85.6% of all enrolled college and university students in the U.S. are undergraduates. A random sample of 500 enrolled college students in a particular state revealed that 420 of them were undergraduates. Is there sufficient evidence to conclude that the ...

### Urgent =Math

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

### stats

In a straight 3 lottery you choose a 3 digit number. A 3 digit number is chosen at random, If your number mataches you win \$250. 1. There are two outcimes in the sample space(\$250,\$0) using these write down a probability model for the straigjt pick three lottery. SOMEONE ...

### math

One light bulb is selected at random from a lot of 150 light bulbs, of which 6% are defective. What is the probability that the light bulb selected is defective?

### statistics

suppose that 70% of all college students love math. in a random sample of 8 college students, let x be the number of students who love math.find p(x=6)

### math

2 students are chosen at random from a group of 120 students that has 60 boys and 60 girls. What is the probability that the students are either both boys or both girls

### statistics

Of the 300 employees that were surveyed, 200 had college degrees, 50 were single, and 30 were both single and had college degrees. What is the probability that an employee chosen at random is single or has a college degree?

### Math

There are 7 rap songs, 7 rock songs and 5 classical songs to select from. Three songs are to be chosento play at random -what is the probability that only classical songs are selected? -what is the expected number of classical songs to be selected?

### Statistics

A newspaper article stated that college students at a local university spent an average of \$95 on beer a year. A student investigator who believed the average stated was too high polled a random sample of 50 students and found a mean of \$92.25 and s = 10 Use these results to ...

### calculus

according to data released by the chamber of commerce of a certain city, the weekly wages of female factory workers are normally distributed with a mean of 575 and a standard deviation of 50. Find the probability that a female factory worker selected at random from the city ...

### statistics

2. The Occupational Safety and Health Administration (OSHA) estimates that roughly 30% of all worker compensation claims stem from back injuries. This statement was made many years ago and you want to know if this has changed in recent years. Suppose you take a random sample ...

### Algebra

Click on "Explain" if you need help. A dart hits the circular dartboard shown below at a random point. Find the probability that the dart lands in the shaded square region. The radius of the dartboard is 5in, and each side of the shaded region is 3in. Use the value 3.14 for...

### Algebra

Click on "Explain" if you need help. A dart hits the square dartboard shown below at a random point. Find the probability that the dart lands in the shaded circular region. Each side of the dartboard is 15in , and the radius of the shaded region is 5in . Use the value 3.14 for...

### Algebra, Probability needed ASAP

1: A box contains 95 pink rubber bands and 90 brown rubber bands. You select a rubber band at random from the box. Find each probability. Write the probability as a fraction in simplest form. A). Find the theoretical probability of selecting a pink rubber band. B). Find the ...

### Stats

Assume we draw a simple random sample from a population having a mean of 100 and a standard deviation of 16. What is the probability that a sample mean will be within plus-or-minus two of the population mean for each of the following sample sizes? n = 50 n=100 n=200 n=400

### Math-probability

A simple dartboard has three areas… the main board has a radius of 11 inches, there is a circle with a radius of 5 inches, and the bullseye has a radius of 2 inches. What is the probability of a random dart landing inside the bullseye? Round to the nearest thousandth. I ...

### MATH

A quiz consists of 90 multiple-choice questions, each with 4 possible answers (A, B, C and D). For someone who makes random guess , A is the correct answer for all the questions. If each right answer carries 4 marks and each wrong answer gives -1/4 marks, what probable marks ...

### Probability and Statistics

Random Variables X and Y follow a joint distribution: f(x,y)=(6-x-y)/8 if 0<x<2, 2<y<4 and 0, else Find P(1<Y<3|X=1) I first got the marginal distribution for x and got (3-x)/4 (Integrated from 2 to 4)and then got the conditional dist and got (5-y)/4 and then...