Random variables x and y have the joint density function fxy(x,y)={ (a(2x+y)^2)/20 -1 < x < 1 -3 < y < 3} { 0 elsewhere } a)find the value of the constant a b)find all the second order moments of X and Y c)what are variances of X and Y d)what is the correlation coefficient
1). In an examination the mean score was 80, the standard deviation was 10, and the grades followed a normal distribution. The instructor wants to assign A's to the top 12%. Where should the cutoff point for A's be? (2). A company manufactures electric light bulbs that have an average life of 1000 hours and a standard deviati
(1). A company manufactures electric light bulbs that have an average life of 1000 hours and a standard deviation of 50 hours. Find the probability that a bulb selected at random will have a life span of between 900 and 950 hours. (2). In an examination the mean score was 80, the standard deviation was 10, and the grades foll
1. Determine whether each of the distributions given below represents a probability distribution. Justify your answer. (A) x 1 2 3 4 P(x) 0.25 5/12 1/3 1/6 (B) x 3 6 8 P(x) 0.1 3/5 0.3 (C) x 20 30 40 50 P(x) 0.2 -0.2 0.7 0.3 2. Consider
1) A major hurricane is a hurricane with wind speeds of 111 miles per hour or greater. During the 20th century, the mean number of major hurricanes to strike the U.S. mainland per year was about 0.7. Find the probability that in a given year a) exactly one major hurricane will strike the U.S. mainland, b) at most one major hurr
Suppose 1.5 percent of the antennas on new Nokia cell phones are defective. For a random sample of 200 antennas, find the probability that: a. None of the antennas is defective. b. Three or more of the antennas are defective. Please show in Excel. The accounting department at Weston Materials, Inc., a national manufact
A study of consumer smoking habits includes 169 people in the 18-22 age bracket (46 of whom smoke), 126 people in the 23-30 age bracket (38 of whom smoke), and 100 people in the 31-40 age bracket (22 of whom smoke). If one person is randomly selected from this sample, find the probability of getting someone who is age 23-30 or s
In a certain lottery, five different numbers between 1 and 36 inclusive are drawn. These are the winning numbers. To win the lottery, a person must select the correct 5 numbers in the same order in which they were drawn. What is the probability of winning?
The mean amount purchased by a typical customer at Churchill's Grocery Store is $23.50 with a standard deviation of $5.00. Assume the distribution of amounts purchased follows the normal distribution. For a sample of 50 customers, answer the following questions. a. What is the likelihood the sample mean is at least $25.00? b
An internal study by the Technology Services department at Lahey Electronics revealed company employees receive an average of two emails per hour. Assume the arrival of these emails is approximated by the Poisson distribution. a. What is the probability Linda Lahey, company president, received exactly 1 email between 4 P.M. a
IRS Audits. A sample of 25 returns is selected from young couples between the ages of 20 and 35 who had an adjusted gross income of more than $100,000. Of these 25 returns five had charitable contributions of more than $1,000. Suppose four of these returns are selected for a comprehensive audit. a. Explain why the hyper
In a batch of 8,000 clock radios 9% are defective. A sample of 15 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 be rejected?
In a certain class of students, there are 9 boys from Wilmette, 5 girls from Kenilworth, 7 girls from Wilmette, 6 boys from Glenco, 5 boys from Kenilworth and 3 girls from Glenoce. If the teacher calls upon a student to answer a question, what is the probability that the student will be from Kenilworth?
A class has 11 students who are to be assigned seating by lot. What is the probability that the students will be arranged in order from shortest to tallest? (Assume that no two students are the same height.)
Based on the table given in the attached file: 1. What is the probability that a consumer selected at random purchased fewer products than before? Round to 4 decimal places. 2. What is the probability that a consumer selected at random purchased the same number or more products than before? Round to 4 decimal places. 3
Based on the table shown in the attached file: 1. On average, what percentage of the people in the fifty states and the District of Columbia does not have health insurance? Round to 2 decimal places. 2. Based on the data above, what is the median percentage of people who do not have health insurance in the fifty states and
The Big Triple at the local racetrack consists of picking the correct order of finish of the first three horses in the ninth race. If there are 12 horses entered in today's ninth race, how many Big Triple outcomes are possible?
Ann is applying for a bank loan to open a pizza franchise. She must first complete a written application and then, if the written application is approved, be interviewed by bank officers. If an applicant's written application is not approved the applicant is not granted an interview with the bank officers. Past records fo
See attached file for additional information. Geoff Brown is the manager for a small telemarketing firm and is evaluating the sales rate of experienced workers in order to set minimum standards for new hires. During the past few weeks, he has recorded the number of successful calls per hour for the staff. These data appear be
See file attached. Using our data set from Unit 1, compose an email to the head of the American Intellectual Union which discusses the following: Begin your email to AIU by first providing an overview of the database, i.e. a story about the characteristics which may include the types of variables included, etc. Be sur
I need help with these specific questions on my homework. I did the rest but can't figure these out. Please include an explanation because I don't want to get behind by not understanding how to solve these questions. I'm already struggling enough - don't need to add more to it. 1. A distribution has a standard deviation of
A firm uses trend projection and seasonal factors to simulate sales for a given time period. It assigns "0" if sales fall, "1" if sales are steady, "2" if sales rise moderately and "3" if sales rise a lot. The simulator generates the following output. 0,1,0,2,2,0,0,1,2,3,2,0,2,0,2,2,1,2,3,1,2,2,2,0,3,0,0,2,1,2,1 Estimate
Learning objectives: distinguish between discrete and continuous random variable; compute statistics about random variable; compute statistics about a function of a random variable; compute statistics about the sum of a linear composite of random variables; identify which type of distribution a given random variable is most like
According to the U.S. Census Bureau, the mean household income in the United States in 2000 was $57,045 and the median household income was $42,148 (U.S. Census Bureau, "Money Income in the United States: 2000," www.census.gov, September 2001). The variability of household income is quite large, with the 10th percentile approxi
The probability that a business owner will go bankrupt in it first year is .34. For 25 like businesses, find the probability first by using the binomial probability formula, and then by using the normal approximation. a. exactly 9 go bankrupt b. No more than 3 go bankrupt
1. There is a 20% probability of rain tomorrow means that: a. Tomorrow it will be raining during 0.2 of the day, and the rest of the day it will be clear. b. Out of the next 5 days, one day it will be raining. c. According to the records, if a weather like one we have today occurred in the past, then 20% of cases it w
See attached file. There are 10 problems. These problems came from a middle school text. Please provide clear explanation so that middle school student can understand how they were solved. 1.A fair coin is flipped four times and the outcomes are recorded. What is the probability that exactly half of the outcomes were tai
A sample of 20 is taken, resulting in a mean of 16.45 and standard deviation of 3.59. Assume that x is normally distributed and used alpha of 0.5 to test hypotheses. ho:u=16 ha:doesn't=16 i know for this problem you would use the p^+or-z(sqaureroot of p times q over n) But i am unsure after you plug those numbers which table
Effectiveness White flies are devastating California crops. An area infested with white flies is to be sprayed with a chemical which is known to be 98% effective for each application. Assume a sample of 1000 flies is checked. Find the approximate probability that no more than 986 of the flies are killed in one application.
1. Probability Type (10.0 points) A ___________ probability is the probability that an event occurs given that another event has already occurred. a) joint b) marginal c) conditional d) exclusive Answer: _____ 2. Probability of Multiple Events (10.0 points) Jim is considering pursuing an MS in Information S