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Statistics : Sampling Distributions and Probabilities

Americans have become increasingly concerned about the rising cost of Medicare. In 1990, the average annual Medicare spending per enrollee was $3267; in 2003, the average annual Medicare spending per enrollee was $6883 (Money, Fall 2003). Suppose you hired a consulting firm to take a sample of fifty 2003 Medicare enrollees to fu


Fifty percent of Americans believed the country was in a recession, even though technically had not shown two straight quarters of negative growth (Business Week, July 30, 2001). For a sample of 20 Americans, make the following calculations. a. Determine the probability that exactly 12 people believed the country was in a re

Probability problem

3. A production line manufactures 1000 ohms resistors that must satisfy a 10% tolerance. a. If a resistance is adequately described by a Gaussian random variable for which mean = 1000; and standard deviation = 40;, what fraction of the resistance expected to be rejected? b. If a machine is not properly adjusted, the produc


In an article about investment growth, Money magazine reported that drug stocks show powerful long-term trends and offer investors unparalleled potential for strong and steady gains. The federal Health Care Financing Administration supports this conclusion through its forecast that annual prescription drug expenditures will reac

Quantitative Methods

Hello Brainmass: Please answer the attached 60 Quantitative methods questions (some are t or f, some are multiple choice). This would be a great study guide for me.


The U.S. Bureau of Labor Statistics collected data on the occupations of workers 25 to 64 years old. The following table shows the number of male and female workers (in millions) in each occupation category (Statistical Abstract of the United States: 2002) (see chart in the attached file) a. Develop a joint probability tab

Binomial Distributions and Z-Scores

1. A door to door salesperson believes that the probability of making a sale when a person is at home is 0.4 he visits 10 homes. When someone is at home find the probability of making a) exactly 7 sales b) more than 7 sales 2.For a binomial distribution with an n=200 and p=0.3 calculate the probability of obtaining between 50

Probability Theory

Indicate whether the sentence or statement is true or false. T 1. Deterministic techniques assume that no uncertainty exists in model parameters. F 2. The probabilities of mutually exclusive events sum to zero. T 3. A joint probability is the probability that two or more events that are not mutually exclusiv

Simple Probability, Sample Spaces, Events

A couple has three children, assume the likelihood of a boy is the same as a girl: List sample space: {BBB,BBG,BGG,GGG} Event the children are grils: {GGG} Event the couple has one or more boy: {BBB,BBG,BGG} Probability all children are girls: 1/4 Probability the couple has at least one boy: 3/4 Probability the couple ha

Eliminate parameter to find a cartesian equation of the curve

1) The manager of a fast food restaurant determines that the average time that her customers wait for service is 2.5 minutes. a) Find the probability that a customer has to wait for more than 4 mintues. b) Find the probability that a customer is served within the first 2 minutes. Now, this was all worked out, but some ste

Probability & Statistics : Mean, Median and Histograms

9. The price-to-earnings (PE) ratio of a stock is the ratio of a stock's most recent price per share to the stock's earnings per share (averaged over a 12-month period). Listed below are the PE ratios for 40 randomly selected securities traded on the New York Stock Exchange (NYSE) on Wednesday, August 24, 2005. Stock PE R

Combinations and Subsets : Probabilities

A committee consists of 8 married couples. In how many ways can a subcommitee of 5 people be chosen so that at most one married couple belongs to the subcommittee?

Process Flow Time - Queueing Problem and Critical Assumptions

See the attached file. Fort Lost-in-the-Woods is a basic training center for new Army recruits. Upon arriving at the military post the new recruits are processed through the Induction Center that involves three steps: background information gathering, medical examination, and barracks assignment. Arriving inductees first enter

Frequency Table

A secretary periodically checks to see how mnay of the three lines into the office are busy. Her findings for one week were the following: No. Lines busy Frequency 0 20 1 65 2 25 3

Probability : Independent Dual Probability

A student applies for two different scholarships. The probability of receiving the first scholarship is 0.3 and the probability of receiving the second is 0.4. The decisions are made independently. Find the probability the student receives exactly one scholarship. A. 0.12 B. 0.42 C. 0.46 D. 0.40

Probability Possibilities Associated with Weapons

The single shot probability of kill of any weapon system (gun, missle or slingshot) is less than 1 due to the reliability factors if no other reason. Suppose the single shot probability of kill of a new defensive missle system is 0.75%, and the the probability is not considered adequate. One familiar strategy to increase the o

Probability : Expected Values and Probability Distributions

According to an automobile manufacturer, the company uses 3,000 lock-and-key combinations on it's vehicles. Suppose that you find a key for one of those cars. a) What is the expected number of vehicles that you would have to check to find one that fits your key? b) What is the probability that you would have to check

Modelling the Rules of a Game

Alex and Mark are playing a game. The goal is to get to 100. The first player picks a whole number from 1 to 10, inclusive, and then the second player picks a whole number from 1 to 10 and adds it to the score so far. The first player repeats this move. They continue this way. The player who makes the score exactly 100 wins.

Probability / Statistics : Combination Application Word Problems

In a marketing survey, consumers are asked to give their first three choices, of 9 different drinks. In how many different ways can they indicate their choices? Find the present value of an ordinary annuity with annual payments of $1,000, for 6 years, at 10% interest compounded annually. A class consists of 15 students.

Probability and Expected Value.

The numbers 1 through 9 are written individually on nine cards. Choose three cards from the nine, letting x, y, and z denote the numbers of the cards arranged in increasing order. A. There are ____ ____ such as x, y, and z combinations. B. The probability of having x, y, and z all even is . C. The probability of ha

Probability Mass Function, Mean and Variance

A lot consisting of 100 fuses is inspected by the following procedure: 5 fuses are selected randomly, and if all 5 "blow" at the specified amperage, the lot is accepted. Suppose that the lot contains 10 defective fuses. Find the probabily of accepting the lot. HINT: Let X ba a r.v. equil to the number of defective fuses in

Probability to find a partner

The Question is: In the game of bridge, each of 4 players is dealt 13 cards. If a certain player has no aces, find the probability that that person's partner has: a.)no aces b.)at least 2