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# Probability

### Statistics of statistics class

Of the students who have registered for a statistics class, 20% are business majors, 30% are finance majors, and the remainder are economics majors. 60% of the business majors are graduate students, 40% of finance majors are graduate students, and 30% of the economics majors are graduate students. (a) (4 points)What percentag

### Probability Of Different Courses Being Ordered

1. Pizza House offers 4 different salads, 5 different kinds of pizza, and 4 different desserts. How many different three course meals can be ordered? 2. Assume the probability is ½ that a child born is a girl. If a family has three children, what is the probability that they have: a. Exactly one girl b. At most tw

### Normal distributions and Z scores Box plot and relation to normal distribution Grading on a curve. Pros and Cons.

Give an example from everyday life where you could use the Normal distribution to determine the probability of something. What is a z score and how could calculating a z help you in a business situation? How does a box plot relate to the normal distribution? In what ways are they similar? In what ways are they differen

### Discrete Probability Distributions

The amount of a brand of soda in 12-ounces can is approx. normal with a mean of 12.1 ounces and a standard deviation of 0.15 ounces. (A) What is the probability that a randomly chosen can contains more than 12.3 ounces? Less than 11.9 ounces? (B) What percentage of the soda can contains less than the advertised 12 ounces?

### Discrete Probability Distributions- Normal probability

The one-mile running time for CMS male athletes is approx. distributed normally with a mean of 7.5 minutes and a standard deviation of 0.6 mins. (A) What percentage of athletes run a mile in less than 7 minutes? In less than 8 mins? In more than 6.5? Between 7 and 8 mins? (B) If a male athlete is randomly chosen, what is the

### Statistics and Successful Surgical Techniques

A surgical technique is performed on eight patients. You are told there is an 80% chance of success. a. Graph the binomial distribution using a relative frequency histogram b. Find the mean and standard deviation of the distribution c. What is the probability that the procedure is successful for exactly (2n)/2 patients if the

### Normal Distribution of SAT Verbal Scores

SAT Verbal Scores are normally distributed with a mean of 430 and standard deviation of 120, fined the following: a. If one of the students is randomly selected, find the probability that student's Score is more than (440 + n) b. If 100 students are randomly selected, find the probability that their mean score is more than (44

### Probability of Defective Computer Chips

The Binary Computer Company manufactures computer chips used in DVD players. Those chips are made with a (27 + n)% yield meaning that (27 + n)% of them are good and others are defective. a. If one chip is randomly selected, find the probability that it is not good. b. If two chips are randomly selected, find the probability th

### Statistics: Poisson distribution

In the example: P(x; &#956;) = (e-&#956;) (&#956;x) / x! P(3; 2) = (2.71828-2) (23) / 3! P(3; 2) = (0.13534) (8) / 6 P(3; 2) = 0.180 Where 3! = 6, how was that number calculated? In the example: P(x < 3, 5) = P(0; 5) + P(1; 5) + P(2; 5) + P(3; 5) P(x < 3, 5) = [ (e-5)(50) / 0! ] + [ (e-5)(51) / 1! ] + [ (e-5)(52) /

### Statistics: Calculating the Probability of High Blood Pressure

Question: Of 1338 people who came into a blood bank to give blood, 253 people had high blood pressure. Estimate the probability that the next person who comes in to give blood will have high blood pressure.

### Binomial Probability: Unfair Coin Flip

11) Suppose an unfair coin comes up tails 42% of the time if it is flipped. If the coin is flipped 13 times, what is the probability that? a) it comes up tails exactly 5 times. b) it comes up tails less than 4 times.

### Statistics: mean, variance, standard deviation of die roll, defective bolts, blue parakeet

1) In a survey, 55% of the voters support a particular referendum. If 40 voters are chosen at random, and X is the number of voters that support this referendum, find the mean and variance of X. Place the mean in the first blank_______________ and place the variance in the second blank____________________________ 2) A die is

### Normal Probability: Weights of Pumpkins

See the data file attached. John's Colorado farm grows some of the finest pumpkins around. Assume weights of pumpkins follow the normal probability distribution with a population weight of 16.0 lbs with a standard deviation of 3.65 lbs. Use Appendix D (posted with statistical tables in the course materials forum) or standard

### Statistic Problems and Descriptive Question

I managed to do all my other questions but I cannot figure these specific problems out. They are not fully explained in the book and I cannot figure it out by searching for help online. I have worked all day yesterday and most of today on this and just cannot get these specific problems! If you could explain how to do them with

### Statistics: Find the probabilities, construct a distribution, classify as discrete or random

See attached file. 1. Find the following probabilities: (A) Events A and B are mutually exclusive events defined on a common sample space. If P (A) = 0.3 and P(A or B) = 0.40, find P(B). (B) Events A and B are defined on a common sample space. If P(A) = 0.50, P(B) = 0.50, and P(A or B) = 0.60, find P(A and B) 2. A ba

### ANOVA and Regression Calculations

Case Study of ZYX Incorporated Case Study of ZYX Incorporated Executive Summary The below details is a summary of the research and findings that was completed by Team B Enterprises. This study was conducted with the employees to determine the job satisfaction and stress level of the recently announced move to a new locat

### 2 STATS

I NEED THEM BACK WITHIN 1 HR FROM NOW.SEE DATAS CAREFULLY. 1.According to Investment Digest (&quot;Diversification and the Risk/Reward Relationship&quot;, Winter 1994, 1-3), the mean of the annual return for common stocks from 1926 to 1992 was 15.4%, and the standard deviation of the annual return was 24.5%; During the same

### Quantitative Analysis for Management (10th ed.)

From historical data, Harry's Car Wash estimates that dirty cars arrive at the rate of 10 per hour all day Saturday. With a crew working the wash line, Harry figures that cars can be cleaned at the rate of one every 5 minutes. One car at a time is cleaned in this example of a single-channel waiting line. Assuming Poisson arriva

### Probability Distribution Represented

Determine whether each of the distributions given below represents a probability distribution. Justify your answer. (A) x 1 2 3 4 ______________________________ P(x) 1/12 5/12 1/3 1/12 (B) x 3 6 8 __________________________ P(x) 2/10 0.5 1/5

### Normal Probability Distributions: Credit Card Example

1. (TCO 4) What is the probability that the student is a sophomore given he doesn't carry a credit card? Credit Card Carrier Not a Credit Card Carrier Total Freshman: 33 27 60 Sophomore: 6

### Bivariate density function: Computation of Moments

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

### Normal Probability: Life span of bulbs & Cut off mark..

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

### Statistics: life span of electric light bulbs; normal distribution of student scores

(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

### Statistics: Probability Distributions, Binomial Distribution

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

### Poisson Probability: Major Hurricanes

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

### Statistics and Probability: Defective Nokia Cell Phone & Antennas; Assembly Times For Weston

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

### Statistics: Indicated Probability in consumer smoking habits

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

### Statistics: What is the probability of winning the lottery?

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.

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

### Emails received by Lahey Electronics employees: test probabilities

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