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Coin Flip Probabilities

A first coin (coin #1) that has a probability p of coming up heads is tossed n times. When the first coin (coin #1) comes up heads another coin (coin #2) that has a probability r of coming up heads is tossed. Let Z be the random variable giving the number of times the second biased coin (coin #2) comes up heads. What is the

Probability that defective radio returned to store came from


Probability that US resident is 25-44 years old, older than 24

The following table contains information on the 2002 resident population of the U.S., by age. (Source: The New York Times Almanac 2004, page 277.) Age: < 18 18 - 24 25 - 44 45 - 64 65 + Questions Number in Thousands 1107108 452196 1270419 1068243 588542 If a resident of the U.S. is chosen at rando

Probability: Business Travelers and Golf

A) 40% of business travelers carry either a cell phone or a laptop computer (USA Today, September 12, 2000). For a sample of 15 business travelers, compute the probability that 3 of the travelers carry a cell phone or a laptop. b) Through the week ending September 16, 2001, Tiger Woods was the leading money winner on

Statistics: Probability of women being selected for executive positions

Affirmative action commitments by industrial organizations have led to an increase in the number of women in executive positions. Satellite Office Systems has vacancies for two executives that it will fill from among four women and six men. What is the probability that no woman is selected? What is the probability that at

Sample of 100: How many out of every 1,000 cars assembled should have defects?

A new car was put into production. It involved many assembly tasks. Each car was inspected at the end of the assembly line and the number of defects per unit was recorded. For the first 100 cars produced, there were 40 defective cars. Some of the cars had no defects; a few had one defect, and so on. The distribution of defects f


Suppose Babsie generated the following probability distribution: X p(x) 5 .25 7 .30 10 .25 12 .05 15 .15 a. Is this probability distribution discrete or continuous? Explain your reasoning. b. Calculate the expected value of X. Show your work!! c. Calculate the variance of X. Show your work!!! d.

Probability: Fantasy Sports Example

Suppose 30% of students play fantasy sports, that is, ¼ = 0:3. You have drawn a simple random sample of size 400 from this population. Let p denote the proportion of the sample that play fantasy sports. Compute the probability that for your sample of 400 students, p will fall between .27 to .33 (i.e., within +/- .03 of .3).

Probability: Earthquake Example Problem

Based on the historical earthquake activity provided below, what is the probability that an earthquake with a magnitude of 6.0 or greater will strike Los Angeles in the year 2010 and beyond. Please use at least 5 statistical concepts that you may find applicable to the problem. Concepts I have studied: Standard deviation, Probab


1. Suppose that for a 5-year-old automobile, the probability the engine will need repair in year 6 is 0.3, while the probability that the tires need replacing in year 6 is 0.8. The probability that both the engine will need repair and the tires will need replacing in year 6 is 0.2. What is the probability that the tires will nee

Binomial Distribution: Probability Example Problem

A company has 125 personal computers. The probaility that any one of them will require repair on a given day is 0.15. Assuming that the number of computers that requires repair on a given day follows a bionomial distribution, compare that there will be no more than 8 computers that require repair on a given day.

Uniform Distribution: Time Interval Between Light Bulbs

Suppose the time interval between two consecutive defective light bulbs from a production line has a uniform distribution over an interval from 0 to 90 minutes. What is the probability that the time interval between consecutive light bulbs will be at least 80 minutes?


A. Assuming that the distribution of IQ is accurately represented by the bell curve in Figure 5.16, determine the proportion of people with IQs in each of the five cognitive classes defined by Herrnstein and Murray. Figure 5.16 The distribution of IQ (See the attachment) b. Although the cognitive classes above are defined

Finance calculations using excel

Our midterm is going to be similar to problems I have posted. I need assistance in completing these type of problems using excel. Can you please assist?


18. Suppose that the sales manager of a large automotive parts distributor wants to estimate as early as April the total annual sales of a region. On the basis of regional sales, the total sales for the company can also be estimated. If, based on past experience, it is found that the April estimates of annual sales are reasonabl

Probability a Student is an Engineering Major

At a certain college, there were 600 science majors, 200 engineering majors, and 500 business majors. If a student is selected at random, what is the probability that the student is an engineering major?

Cherry Trees: Computing the Probability

The average height of flowering cherry trees in a nursery is 11 feet. If the heights are normally distributed with a standard deviation of 1.6, find the probability that a randomly selected cherry tree in this nursery is less than 13 feet tall.

Time to finish the job

An employer wants to set a time limit so that 90% of the employees will finish a job on time. Past history has shown that the time required to do the job is normally distributed and has a mean time of 28 minutes with a standard deviation of 5 minutes. How much time should the employer allow employees to finish the job? (Round

Z-Score and Probability

1: Given the standardized normal distribution (with a mean of 0 and a standard deviation of 1, as in table E.2), what is the probability that A: Z is less than 1.57? B: Z is greater than 1.84? C: Z is between 1.57 and 1.84? D: Z is less than 1.57 or greater than 1.84? 2: The breaking strength of plastic bags used for p

Statistics Quantitative Analysis: Probability and frequency distribution

Probability A certain state is contemplating creating a weekly lottery, the revenues from which will be used to fund improvements in the state's public education system. The commission chartered to develop the guidelines for the proposed lottery envisions using a process whereby six (6) balls will be randomly selected from a

Statistics: Probability Example Questions

1: When a customer places an order with Rudy's On-Line Office Supplies, a computerized accounting information system (AIS) automatically checks to see if the customer has exceeded his or her credit limit. Past records indicate that the probability of customers exceeding their credit limit is 0.05. Suppose that, on a given d

Calculating premium amount

Accident records given by an insurance company give the following information. The probability that an insured driver has an accident is 0.15. If an accident occurs, the damage to the vehicle amount to 20% of its market value 80% of the time, to 60% of its market value with probability 0.12, and a total loss with a probability o

Probability of Rejecting the Ledger

An auditor takes samples from ledgers to decide whether to certify or reject the ledger. The sampling method used is to select 10 entries at random from the ledgers and then analyze each for errors. If the auditor finds no errors he certifies the ledger. If he finds 2 or more entries with errors he rejects the ledgers. If the au

Probability calculations considering Obama's health care plan

Consider Obama's health care plan. There are = #s of males and females. 50% of the females approve (A) of the plan and 70% of the males do not approve (N) of the plan. If a simple random sample of 1 person is selected from the population determine: P(A/M) P(A) P(F U A) P(F/A)

Probability Distribution: Temperature Example

High temp for January 1st is normally distributed with a mean of 40 degrees and a standard deviation of 5 degrees. Determine the probability that the Jan 1st high temp will be exactly 40 degrees. Determine the probability that the Jan 1st temp will be above 48 degrees. If Jan 2nd has the same high temp probability dis


According to the "January theory," if the stock market is up for the month of January, it will be up for the year. If it is down in January, it will be down for the year. According to an article in The Wall Street Journal, this theory held for 28 out of the last 34 years. Suppose there is no truth to this theory; that is, the pr