random
4,688 results, page 20

statistics
A simple random sample of a size n is drawn from a population that is normally distributed. The sample mean, x is found to be 110, and the sample standard deviation, s, is found to be 10. A Construct a 95% confidence interval about u if the sample size, n, is 17 
Math
Find the probability using combinations.A bag contains 6 cherry, 3 orange and 2 lemon candies. You reach in and take 3 pieces of candy at random. Find the probability that you have all cherry candies. 
PreCalc
Three cards are chosen at random from a standard 52card deck. Find the probability that all three cards are hearts given that there are 13 hearts in the deck. Round to the nearest thousandth. Is this 0.013? 
Probability Help ASAP!
Giving a test to a group of students, the grades and gender are summarized below A B C Total Male 17 5 2 24 Female 7 11 12 30 Total 24 16 14 54 If one student was chosen at random, find the probability that the student was female. 
College Math
Four balls are selected at random without replacement from an urn containing four white balls and five blue balls. Find the probability of the given event. All of the balls are blue. 
Statistics
The table to the right lists probabilities for the corresponding numbers of girls in three births. What is the random variable, what are its possible values, and are its values numerical? Number of girls x P(x) 0 0.125 1 0.375 2 0.375 3 0.125 
statistics
A student claims the average amount of time spent studying for an exam is less than or equal to 120 minutes. A random sample of 101 students is drawn from a normal distribution. The sample mean is 140 with a sample standard deviation of 20. Test the claim with a .01 level of ... 
math
In a clinical trial, a drug used to reduce blood pressure caused side effects in 6% of the patients who took it. For a new rial, two patients were selected at random. Find the probability that both the patients had side effects. 
math
In a clinical trial, a drug used to reduce blood pressure caused side effects in 6% of the patients who took it. For a new rial, two patients were selected at random. Find the probability that both the patients had side effects. 
Statics
A random sample of 100 cans of peaches has an observed mean weight of 48.5 ounces and a standard deviation of 2.4 ounces. Determine the lower limit of the 95% interval for the true mean weight. The can label says that the can weights 48 ounces. Comment on this claim. 
stat.
The average age of a vehicle registered in the United States is 8 years, or 96 months. Assume the standard deviation is 16 months. If a random sample of a group of 48 vehicles is selected find the probability that the mean of the group’s age is between 90 and 100 months. 
statistics
The average age of a vehicle registered in the United States is 8 years, or 96 months. Assume the standard deviation is 16 months. If a random sample of a group of 48 vehicles is selected find the probability that the mean of the group’s age is between 90 and 100 months. 
probability
The random variables X and Y have the joint PMF pX,Y(x,y)={c⋅(x+y)2,0,if x∈{1,2,4} and y∈{1,3},otherwise. All answers in this problem should be numerical. Find the value of the constant c. c= Find P(Y<X). P(Y<X)= Find P(Y=X). P(Y=X)= Find the following ... 
statistics
The Redsox were accused of cheating their soda customers by not putting enough soda in the 12 ounce cup. When 15 cups were selected at random, they were found to have a mean of 11.7 ounces with a standard deviation of 0.5 ounces. At the .01 significance level, test the claim ... 
PROBABILITY MATH
An unprepared student makes random guesses for the ten truefalse questions on a quiz. Find the probability that there is at least one correct answer. Could some one please help me? And explain to me how they got the answer? and is there another way besides the tree method? 
Statistics & Probability
If X is a normal random variable with mean 11, and if the probability that X is less than 12.10 is .72 , then what is the standard deviation of X? Select one: a. 3.00 b. 6.25 c. 2.50 d. 1.25 Please note that the answer for the above is stated as c.2.50. However, my answer ... 
Math (Statistics)
The SAT scores of a certain population of students are approximately normally distributed with a mean and standard deviation of 1000 and 200 points, respectively. The probability that a student selected at random from the population has an SAT score between 800 and 1200 ... 
Quantitative Analysis
The students at Littlewood Regional High School cut an average of 3.3 classes per week. A random sample of 117 seniors averages 3.8 cuts per week, with a standard deviation of 0.53. Are seniors significantly different from the student body as a whole? 
Math
Identify the sampling,method. You want to determine the number of text messages students at your school send in a month. You go to the cafeteria and ask every 4th student that walks in. a random b systemic c stratified dm none of these My answer is none of the these ... 
Mathematics Help
Giving a test to a group of students, the grades and genders are summarized below. A B C Total Male 3 15 11 29 Female 14 9 12 35 Total 17 24 23 64 If one student is chosen at random, find the probability that the student was female OR received a grade of "C". (Leave answer to ... 
statistics
Suppose the average weight for population of men is 178 pounds. You draw a random sample of 10 men and record the following weights: 150, 145, 180, 200, 175, 190, 142, 175, 240, 150. Calculate the sampling error. 
Math
you want to determine the average age when people got their driver's licence you want to collect data from a random sample of at least 400 people Which of these is most valid for collecting data? * Survey an equal number of students of driving age teachers parents and ... 
probability
Suppose 1 person is picked at random from this group of dog owners. The probability that the person chosen is at least 50 years old and has at least 1 dog equals 
LBCC
According to an Internet posting, 65% of adults enjoy drinking soda. Choose a group of 12 adults at random. The probability that none of them enjoy drinking soda is? 
statistics help please :(
A shipment of 50 parts contains 11 defective parts. Suppose 3 parts are selected at random, without replacement, from the shipment. What is the probability that exactly 2 parts are not defective? 
math
A deck of cards are shuffled 20 times. You are dealt 12 cards at random: what is the probability that all 12 cards are black? or what is the probability that all 12 cards are kings, queens or jacks 
stats
shipment of 30 computers, 8 are defective. Four computers are chosen at random. Find the probability that: a)Exactly two are defective b)None are defective c)At most two are defective 
Statistics
If the probability of randomly choosing a county resident from a class of students is 65%, what is the probability of selecting exactly 7 county resident out of a random group of 10 students? 
Statistics
For a particular value, this table gives the percent of scores between the mean and the zvalue of a normally distributed random variable. What percent of the total population is found between the mean and the zscore, assume z = 2.57. PLEASA HELP!!!! 
MathProbability
Michael is one of eight contestants entered in three races to be run on a eightlane track. If in each race the runners are assigned to the lanes at random, what is the probability that Michael will be assigned to the inside lane at least once? 
statistics
A simple random sample size of n = 150 is obtained from a population whose size is N = 20,000 and whose population proportion with a specified characteristic is p = 0.6. What is the probability of obtaining x = 96 or more individuals with the characteristic P(p hat)≥0.64 
statistics
A sample of 100 iron bars is said to be drawn from a large number of bars. Whose lengths are normally distributed with mean 4 feet and S.D 0.6ft. If the sample mean is 4.2 ft, can the sample be regarded as a truly random sample? 
math
A bag contains x marbles. Half of the marbles are blue. Four less than the number of blue marbles are red. The remaining marbles are purple. What is the probability of choosing a purple marble at random? a. 2 b. 4 c. 1/2(x/24)/x d. x/24 e. x/2 please answer and explain 
Statistics
Selecting a letter of the alphabet: If 3 letters of the alphabet are selected at random, find the probability of getting at least one letter "x". Letters can be used more than once. My answer was: P(at least 1 "x) = 1  (25/26)^3 = 1951/17576 or 0.11 Is this correct? 
Math
Voting In a survey of 350 registered voters in belair,123 said that they would vote for the democratic candidate for mayor. if registered voter is selected at random, what is the probability that this person will vote for the democratic candidate. 
MATH
A quiz consists of 90 multiplechoice questions, each with 4 possible answers (A, B, C and D). For someone who makes random guesses for all of the answers, find the probability of getting A as right answer. A is the correct answer for all the questions 
Digits
You pick 2 digits (09) at random without replacement, and write them in the order picked. What is the probability that you have written the first 2 digits of your phone number? Assume there are no repeats of digits in your phone number. Give your answer as a fraction. 
Math
A weather forecast states that there is a 20% probability of rain on each of the next 3 days. Describe a simulation you could perform using random numbers to find the experimental probability that it will not rain on any of the next 3 days. Would love explanation! 
Statistics
Suppose the heights of 18yearold men are approximately normally distributed, with mean 66 inches and standard deviation 4 inches. (a) What is the probability that an 18yearold man selected at random is between 65 and 67 inches tall? (Round your answer to four decimal ... 
Statistics
In a random sample of 508 judges, it was found that 281 were introverts. Let p represent the proportion of all judges who are introverts. Find a point estimate for p. Round your answer to four decimal places. I am needing assitance in trying to figure out the correct formula ... 
math (stats)
A biology professor gives a surprise quiz consist of a true/false question followed by a multiple choice question with four possible answers. If both questions are answered with random guesses, find the probability that both responses are correct. Please show your work. 
Statistics
A random sample of 10 independent observations from a normally distributed population yielded the following values 51, 53, 49, 43, 47, 46, 45, 30, 60, 52. a) Estimate the standard deviation of the sampling distribution of means for samples like this one. b) Using á = .05, ... 
statistics
A politician claims that she will receive 66% of the vote in an upcoming election. The results of a properly designed random sample of 145 voters showed that 80 of those sampled will vote for her. Is it likely that her assertion is correct at the 0.01 level of significance? ... 
math 120
A recent poll of a random sample of 400 students at a public 4year college showed the average (mean) amount of time spent using email was 49 minutes per day with a standard deviation of 44 minutes. a. find a 95% confidence interval fot the population mean 
statistics
a repair shop believes that people travel more than 3500 miles between oil changes a random sample of 8 cars getting an oil change has average distance of 3375 standard deviation of 225 miles with alpha 0.05 is there enough evidence to support the shops claim 
Algebra 2
A random sample of 5000 people was chosen for a survey. 54% of them said they didn't have children under 18 living at home. Find the 95% confidence interval. Round answer to 4 significant digits and give lowest and highest values of confidence Interval. I got 200.9 & 339.0 but... 
math
The diameters of pencils produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches. In a random sample of 460 pencils, approximately how many would you expect to have a diameter less than 0.293 inches? A. 123 B. ... 
math
A professor knows that in her class 37% of the students have passed an Algebra course, 29% have passed an English course, and 21% have passed both courses. If one student is selected at random from this class, find the probability that: 
Math
A box contains 3 red marbles, 6 blue marbles, and 1 white marble. The marbles are selected at random, one at a time, and are not replaced. Find the probability. P(red and blue and blue) Please help me 
Math
There are 3,000 people at a concert. You survey a random sample of 200 people and find that for 35 of them this is the first concert they have ever attended. Estimate how many people are attending their first concert that night. 
Math157
If a student is selected at random, what is the probability he or she prefers meat toppings ? 68 students prefer cheese 79 students prefer meat 70 students prefer veggie 70/208, 35/104 or 1/3 is that correct ? 
Algebra 2
How do I answer this f(x) = x  3 (x + 4)^(1/2) and am asked how to solve for x when y = 5 I have no idea how to do this and know that I could just solve it by guess and checking but I want to know how to do this algebraically when plugging in the 5 and trying to solve for x... 
math check answer
If a student is selected at random, what is the probability he or she prefers meat toppings ? 68 students prefer cheese 79 students prefer meat 70 students prefer veggie 70/208, 35/104 or 1/3 is that correct 
Math/Statistics
A simple dartboard has three areas…the main board has a radius of 8 inches, there is a circle with a radius of 6 inches, and the bullseye has a radius of 4 inches. What is the probability of a random dart landing inside the bullseye? 
maths
Suppose that a state university has to form a committee of 5 members from a list of 20 candidates out of whom 12 are teachers and 8 are students.If members of the committee are selected at random,what is the probability that the majority of the committee members are students? 
maths
Suppose that a state university has to form a committee of 5 members from a list of 20 candidates out of whom 12 are teachers and 8 are students.If members of the committee are selected at random,what is the probability that the majority of the committee members are students? 
Math
There are 3,000 people at a concert. You survey a random sample of 200 people and find that for 35 of them this is the first concert they have ever attenede. Estimate how many total people are attending their first concert that night 
probability
Consider n independent rolls of a ksided fair die with k≥2: the sides of the die are labelled 1,2,…,k and each side has probability 1/k of facing up after a roll. Let the random variable Xi denote the number of rolls that result in side i facing up. Thus, the random ... 
statistics
A random sample of 20 hogs on farmer Brown's hog farm had an average weight of 350 pounds and a SD of 70 pounds. Find 95% confidence interval estimate of the mean weight of all farmer Brown's pigs. 
statistics
The average age of a vehicle registered in the U.S. is 8 years, or 96 months. If a random sample of 36 vehicles is selected, find the probability that the mean of their age is between 98 and 100 months. Assume the standard deviation for the population is 15. (sample mean) 
statistics
Lubbock, Texas ran a survey and determined that 27% of all households subscribed to the daily paper, 32% watched the evening news, and 9% did both. If a household is chosen at random, what is the probability that the evening paper was received or the news was watched? 
statistics
dole pineapple inc. is concerned that the 16 ounce cans are overfilled. assume the standard deviation is .03 onces. a random sample of 50 cans has a mean weight of 16.05 ounces. at the 5% level of significance can we conclude that the mean weight is > than 16 ounces. what ... 
math
In a random sample of 1,000 exams, the average score was 500 points with a standard deviation of 80 points. Find the interval about the sample mean such that the probability is 0.90 that the mean number lies within the interval. 
statistics
A random sample of 84 shoppers were interviewed and 51 said they prefer to shop alone rather than with someone else. Let p represent the proportion of all shoppers at this mall who would prefer to shop alone. Find a point estimate (p hat) for p. 
Statisics
35%of adult Americans are regular voters. A random sample of 250 adults in a mediumsize college town were surveyed, and it was found that 110 were regular voters. Estimate the true proportion of regular voters with 90% confidence and comment on your results... Can you show ... 
Business
For a continuous random variable x, the population mean and the population standard deviation are 80 and 15 respectively. You extract a sample of 25 elements from this population. The mean of the sampling distribution of the sample mean is 
Data managment math
2:Hoyda has 15 percent of the car market. If a random sample of 20 auto mobiles is conducted what is the probabilitity that (a) exactly one of the car was made by hoyda (b) atleast two of the car were made by hoyda. 
Maths
Among the examinees in an examination 30%, 35% and 45% failed in Statistics, in Mathematics, and in at least one of the subjects respectively. An examinee is selected at random. Find the probabilities that a. He failed in Mathematics only b. He passed in Statistics, if it is ... 
statistics
In a survey, 63% of Americans said they own an answering machine. If 14 Americans are selected at random, find the probability that exactly 9 own an answering machine. 
Math
In your own line of work, give one example of a discrete and one example of a continuous random variable, and describe why each is continuous or discrete. 
Math Statistics
Suppose 60% of adults have a college degree. If I take a random sample of 80 adults, what is the probability at least 50% of them have a college degree? 
Maths
There are 12 balls in a bag, where n of them are white balls. If 2 balls are chosen at random from the bag without replacement, the probability of choosing at least 1 white balls is 19/33. Find n. 
statistics
A shipment of 50 parts contains 12 defective parts. Suppose 3 parts are selected at random, without replacement, from the shipment. What is the probability that all 3 parts are defective? 
Prealgebra
I can't figure out how to solve: Question #1: Two number cubes are rolled and a coin is tossed. Find the number of possible outcomes. Question #2: What is the probability of winning a lottery game where the winning number is made up of 6 digits from 09 chosen at random. 
statistics
A random samples of 250 bolts manufactured by machine A and 200 bolts manufactured by machine B showed 24 and 10 defective bolts respectively. Test the hypothesis that the machines are showing difference qualities of performance. Use 5 per cent level of significance. 
Statistic
The amount of time it takes to take your order at the local Whaters restaurant has a population mean m of 3.1 minutes and a standard deviation s of 0.40 minutes. If you select a random sample of 16 customers: Q3a: What is the probability that the mean time spent per customer ... 
math
A high school guidance counselor conducts a survey to find the student's first choice for a college major and found that 65% of students choose math. If three students are chosen at a random, what is the probability that at least one of them would choose math? 
PRECALC
A number is selected at random from the set {2, 3, 4, … ,10}. Which event, by definition, covers the entire sample space of this experiment? A) The number is greater than 2. B) The number is not divisible by 5. C) The number is even or less than 12. D) The number is neither ... 
math
You plan to visit two different zoos but cannot decide which two to visit. On a piece of paper,you write the name of each zoo in the table. Then you select the names of two zoos at random. Are your selections independent or dependent events. Explain. B. What is P (Smithsonian... 
math 12
A manufacturer of cereal finds that the masses of cereal in a company's 200g package are normally distributed with a mean of 200g and a standard deviation of 16.3g a) What proportion of these boxes contain between 183.7g and 216.3g of cereal? b) What is the probability that a... 
statistics
Let X be the average of a sample of size 25 independent normal random variables with mean 0 and variance 1. P[[X<c]=0.5 (a) Determine c such that (b) Now assume that the observations may not be normally distributed, but they still are independent with mean 0 and variance 1... 
Algebra
I don't quite understand how to solve matrices with three variables. If I have the equations: 7x4y2z=0 2x3y+z=0.25 2x2y+5z=0 How can I solve this? I saw the explanation in a site but I didn't understand it. They appeared to make random operations until the matrix was: 1 ... 
science
List the five conditions that can disturb genetic equilibrium in a population I think Infinite population size, no mutation, no selection against a certain homozygous gene, random mating, no immigration/emigration Mutations. can someone let me know if this is right or not? if ... 
statistical reasoning
One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent. The following counts were observed. Colorblind Not Colorblind Total Male 8 52 60 Female 2 38 40 Total 10 90 100 Find the value of the X2 ... 
IGNOU probability
Among the examinees in an examination 30%, 35% and 45% failed in Statistics, in Mathematics, and in at least one of the subjects respectively. An examinee is selected at random. Find the probabilities that a. He failed in Mathematics only b. He passed in Statistics, if it is ... 
Math
From a sample set of 10 colored balls5 green, 3 red and 2 yellow 5 are chosen at random WITH replacement. What is the probability that the result will be: green, red, yellow, red, green? Write your answer as a four place decimal number. p(G,R,Y,R,G) 
math
a box contains seven red marbles, five green marbles & eight blue marble. a marble is drawn at random & is replaced. a second marble is then draw from the jar. find the probabilty that both marbles are green 
Quantitative methods for business
Suppose that a state university has to form a committee of 5 members from a list of 20 candidates out of whom 12 are teachers and 8 are students.If members of the committee are selected at random, what is the probability that the majority of the committee members are students? 
PreCalculus
Consider a class with 10 sophomores, 8 juniors, and 6 seniors. Two students are selected at random. 1) What is the probability of selecting 1 junior and 1 senior. 2) Find the odds of selecting two students who are not seniors. How do I set these up to solve?? Any help is ... 
statistics
A transportation company wants to estimate the variance of the length of time goods are in transit across the country. A random sample of 20 shipments gives days and day. Give a 95% confidence interval for the variance of the transit time for all goods. 
statistics
The director of a health club conducted a survey and found that 23% of memebers used only the pool for workouts. Based on this information, what is the probablity that for a random sample of 10 members, 4 used only the pool for workouts? Please show work Thank you 
statistics
once again I am not getting this. assume that the population of heights of male college students is normally distibuted with a mean of 69.09 and standard deviation of 4.71. A random sample of 92 heights is obtained. find the mean and standard error of the x distribution. find ... 
Algebra 2
In a quiz program, 3 questions on sprots, 3 questions on general knowledge, and 4 questions on science are printed separately on 10 cards and placed upside down. John is asked to select 2 cards at random. What is the probability of Joohn selecting 2 questions on science? 
Probability
A boy forgot his password for his Internet gsme account. He has a total of 8 paaswords for various accounts. If he tries these passwords at random,one by one without repetition , what is the probability that he will log in to his Internet game account within 2 attempts ? 
Probability
A group of 90 students is to be split at random into 3 classes of equal size. All partitions are equally likely. Joe and Jane are members of the 90student group. Find the probability that Joe and Jane end up in the same class. 
problem and statistics
In a random sample of 10 online statistics students, information was collected about their minutes studied and their chapter test scores. X is the minutes studied, and Y is the test score. x : {20,30,45,60,80,90,45,120,90,70} y: {50,45,55,70,80,90,80,100,95,85} Is this ... 
Statistics
The average SAT score for the 300 students accepted at Tiny College this year is 1,050 with a standard deviation of 275. If a random sample of 40 students is selected from this class, what is the probability that the average SAT score will be greater than 1,000? 
math
A factory finds out that on the average 20% of bolts produced by the given machine will be defective.if 10 bolts are selected at random from the day's production of this machine,find the probability that 1.exactly 2 will be defective. (this question is base on probability and ... 
Math
A bag contains 5 balls,8 white balls, 9 green balls,7 blue balls& 6 yellow balls.A ball is drawn at random .Find the probablity that the ball in neither green nor red ? 
Math
At his school’s field day, 7 of Jake’s classmates won a bronze trophy, 14 won a silver trophy, and 10 won a gold trophy. If you choose one trophy winner at random, what is the probability that you would choose someone who won a bronze trophy?