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Probability

the probability of guessing exact birth date

If you are told that a randomly selected mystery person was born in the 1990's, what is the probability of guessing his/her exact birth date (including year)?

Probability: Is the Statement True?

If P(A|B) < P(A), then it is true that: a. P(A) < P(B) b. P(B) < P(A) c. P(A) < P(The intersection of A and B) d. P(A|B) < P(The intersection of A and B) e. P(B|A) < P(B)

Statistics Problems solved in this posting are based on Poisson Distribution and Normal Distribution. For Specific Problems, please see the posted problems.

Use the Poisson Distribution to find the indicated probability. 49) For a certain type of fabric, the average number of defects in each square foot of fabric is 0.3. Find the probability that a randomly selected square foot of the fabric will contain more than one defect. 49) ______ A) 0.0369 B)

28) A contractor is considering a sale that promises a profit of \$ 23,000 with a probability of 0.7 or a loss (due to bad weather, strikes, and such) of \$ 13,000 with a probability of 0.3. What is the expected profit? 29) Choosing 3 marbles from a box of 40 marbles (20 purple, 12 red, and 8 green) one at a time with replacement, keeping track of the number of red marbles chosen. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. 33) n = 4, x = 3, p = 1/6 34) n = 10, x = 2 , p = 0.5 35) n =12, x = 5, p = 0.25 36) A test consists of 10 true/false questions. To pass the test a student must answer at least 7 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test? 37) Find the probability of at least 2 girls in 10 births. Assume that male and female births are equally likely and that the births are independent events. 38) An airline estimates that 98% of people booked on their flights actually show up. If the airline books 76 people on a flight for which the maximum number is 74, what is the probability that the number of people who show up will exceed the capacity of the plane? Find the mean, &#956;, for the binomial distribution which has the stated values of n and p. Round answer to the nearest tenth. 39) n = 33; p = .2 Find the standard deviation, &#963;, for the binomial distribution which has the stated values of n and p. Round your answer to the nearest hundredth. 41) n = 36; p = .2 42) n = 2661; p = .63 43) n = 94, p = 0.20 44) n = 377, p = 2/3 45) According to a college survey, 22% of all students work full time. Find the mean for the number of students who work full time in samples of size 16. 46) A company manufactures batteries in batches of 29 and there is a 3% rate of defects. Find the mean number of defects per batch. Determine if the outcome is unusual. 47) A survey for brand recognition is done and it is determined that 68% of consumers have heard of Dull Computer Company. A survey of 800 randomly selected consumers is to be conducted. For such groups of 800, would it be unusual to get 481 consumers who recognize the Dull Computer Company name? 48) According to AccuData Media Research, 36% of televisions within the Chicago city limits are tuned to "Eyewitness News" at 5:00 pm on Sunday nights. At 5:00 pm on a given Sunday, 2500 such televisions are randomly selected and checked to determine what is being watched. Would it be unusual to find that 872 of the 2500 televisions are tuned to "Eyewitness News"?

Solve the problem. 22) Find the variance for the given probability distribution. 22) ______ A) 2.46 B) 2.69 C) 7.43 D) 2.63 23) Find the standard deviation for the given probability distribution. 23) ______ A) 1.71 B) 1.6

21 prob/stats multiple choice questions

Express the indicated degree of likelihood as a probability value. 1) "You have a 50-50 chance of choosing the correct answer." 1) _______ A) 50 B) 0.50 C) 0.9 D) 0.25 2) "It will definitely turn dark tonight." 2) _______ A) 0.67 B)

Probability of weight distribution of gerbil

The state's smallest animal is a red-tailed gerbil, with a mean weight of 2.5 grams and a standard deviation of 0.25 grams. Assuming that the weights are normally distributed, find the probability of randomly selecting a gerbil that weighs a. between 1.0 and 2.0 grams b. between 1.6 and 2.2 grams c. more than 2.2 grams

Bayes' Theorem for Probability Revision

Set up a short problem related to your work environment to calculate the probability(ies) of an event happening. Then use Bayes' Theorem to revise the probability. Show all your work.

probability of defective circuit card in the sample

Printed circuit cards are placed in a functional test after being populated with semiconductor chips. A lot contains 140 cards, and 20 are selected without replacement for functional testing. a.) If 20 cards are defective, what is the probability that at least 1 defective card is in the sample? b.) If 5 cards are defective,

Probability of Correctly Identifying Defective Items

A company has a 99% chance of correctly identifying defective items and a 0.5% chance of incorrectly saying a good item is defective. The company has evidence that its production is 0.9% defective. a.) What is the probability that an item selected for inspection is classified as defective? b.) If an item randomly selected i

probability that the circuit operates

This electrical circuit operates if and only if there is a path of the functional devices from left to right. The probability that each device functions is as shown. Assume that the probability that a device is functional does not depend on whether or not other devices are functional. What is the probability that the circuit

Discrete & Continuous Probability Distributions

Please use Excel for this and could you send me a few notes with step by step break-down on how to make it easy to figure out next time? 1. An American Society of Investors Survey found that 30% of individuals have used a discount broker. In a random sample of 9 individuals, what is the probability That: a. Exactly 2 of t

Probability - Super Cola sales break down as 80% regular soda and 20% diet soda.

Super Cola sales break down as 80% regular soda and 20% diet soda. While 60% of the regular soda is purchased by men, only 30% of the diet soda is purchased by men. If a woman purchases Super Cola, what is the probability that it is a diet soda? .28902 .30435 .69565 .71098

Probability

A researcher wants to simulate sunny and rainy days in her town for a 3-week period. What is the minimum number of digits the student must obtain from a random number table for each observation if it rained on two-fifths of the days over the past several years at this time of the year? Assume that days can be classified historic

Find probabilities from a data set

Please answer the following probabilities from the data set below using Excel. Also please add them to the chart, Thanks. https://mycampus.aiu-online.com/courses/QMB350/Assignment_Assets/DataSetandDataSetKey_0703A.xls ? What is the gender distribution (% females and % males)? ? What is the "tenure with company" distribut

Statistics - probability

(1) The average number of humming birds per hour on a particular feeder is 5. Find the probability that exactly 3 humming birds feed during a particular hour using the correct table or formula. (2) Weights for students applying to a Sumo wrestling school are normally distributed, with a mean of 250 pounds and a standard dev

Probability - Statistics Binomial Questions

(1) The probability that a house in an urban area will be burglarized is 5%. If 15 houses are randomly selected what is the probability that: (A) Exactly 2 of the houses will be burglarized. (B) Two or fewer houses will be burglarized. (2) The mean monthly gasoline purchase for a family with 2 cars is 62 gallons. This st

This posting provides solution to statistics MCQs focusing on probability, binomial probability distribution, normal probability concepts, etc

Please show all work and examples 1. Under certain conditions, it is possible that the sum of the probabilities of all the sample points in a sample space is less than one. ___ T/F 2. A compound event formed by use of the word and requires the use of the addition rule. ____ T/F 3. In any binomial probability

Problems involving normal distribution, poisson distribution, finding expected value of mean and standard deviation, and finding probability values under normal distributions.

Please show ALL work! 1. Find the following probabilities: a.Events A and B are mutually exclusive events defined on a common sample space. If P (A) = 0.4 and P(A or B) = 0.9, find P(B). b.Events A and B are defined on a common sample space. If P(A) = 0.20, P(B) = 0.40, and P(A or B) = 0.56, find P(A and B) 2.Class

#1 An investment can lead to a profit of \$10,000, \$5,000, \$4,000, and \$1,000, with respective probabilities of .4, .3, .2, and .05. In addition, there is a 3 percent chance of breaking even and a small chance of losing \$10,000. Find the expected profit. #2 A car dealership has combined all popular options available in four

Real Estate Stats Confidence Interval

Assume you have a real estate investor client who wants you to answer some specific questions about housing in the neighborhood encompassed by the 5 townships in your Real Estate Data Set. Further assume that you have collected this random sample in an effort to answer your client's questions using statistical tools.: 1. Des

(1) Find the probability that the elevator will be overloaded if 16 people are in the elevator. (2) How many passengers would you recommend if you wanted to be sure that the overloading probability is less than 0.001?

An elevator has a design capacity of 2,560 pounds and a posted limit of 16 passengers. The weight of adults is approximately normal with a mean of 150 pounds and standard deviation of 20 pounds. Find the probability that the elevator will be overloaded if 16 people are in the elevator. How many passengers would you recommend

Probability Calculations for JENN Inc.

JENN Inc. supplies under-hood emission control air pumps to the automative industry. The pump is vacuum-powered and works while the engine is operating., cleaning the exhaust by pumping extra oxygen into the exhaust system. If a pump fails before the vehicle in which it is installed has traveled 50,000 miles, Federal emission re

Statistics and Process Capability : LSL, USL and CpK

Please help with the following problem. A data set contains 16 measurements as follows: 1525; 1561; 1541; 1532; 1499; 1551; 1554; 1528; 1514; 1548; 1534; 1505; 1500; 1538; 1529; 1519 the calculated mean = 1530 and the calculated std deviation = 19 The USL and LSL are respectively 1560 and 1510 and I, therefore, deri

Discrete and Continuous Probability Distributions

Business Applications When only the value-added time is considered, the time it takes to build a laser printer is thought to be uniformly distributed between 8 and 15 hours. a. What are the chances that it will take more than 10 value-added hours to build a printer? b. How likely is it that a printer will require fewer t

Discrete and Continuious Probability Distribution Practice Problems

5.3 Used the binomial distribution table to callculate the following probabilites for a binomial random variable where n = 20 and p = 0.40 a. p(x = 10) b. p(7< x <12) c. P(x &#8805; 12) 5.29 If &#955; = 5 and t=2 for a Poisson distribution, a. Determine the mean and standard deviation of this Poisson ditribution b. W

Probability Distribution - E-mail Potential Acquisition

E-mail Potential Acquisition You've done a great job so far, but we need you to investigate another situation. BankTen is considering an acquisition and has narrowed the possibilities to three companies. All three of these acquisitions are ongoing businesses with a profit stream and can be acquired for about the same amount o

Probability of selling life insurance

1. The probability that a life insurance salesperson following up a magazine lead will make a sale is 30%. A salesperson has two leads on a certain day. What is the probability that the salesperson will sell: a. Both b. Exactly one policy c. at least one policy

Continuous Probability Distribution at Hydronics Company

DATA ATTACHED The Hydronics Company is in the business of developing health supplements. Recently, the company's R&D department came up with two weight-loss plans that included products produced by Hydroniccs. To determine whether these products are effective, the company has conducted a test. A total of 300 people who eac

Discrete and Continuous Probability Distributions

East-West Translations publishes textbooks of ancient Oriental teachings for English-speaking universities. The company currently is testing a computer-based translation service. Because Oriental symbols are difficult to translate, East-West assumes the computer program will make some errors, but then so do human translators.

Discrete Probability Distributions Gateway 2000 Inc.

5.18 Gateway 2000, Inc., receives large shipments of microprocessors from Intel Corp. It must try to ensure that the proportion of microprocessors that are defective is small. Suppose Gateway decides to test five microprocessors out of a shipment of thousands of them. Suppose that if at least one of the microprocessors is de