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Calculating various probabilities

A new drug cures 80% of the patients to whom it is administered. It is given to 25 patients. Find the probabilities that among these patients, the following results occur. a. Exactly 20 are cured. b. All are cured. c. No one is cured. d. Twelve or fewer are cured.

Statistic and Probability

Hello. Can anybody help e with these 6 example questions that were created. I want to use them as a study guide. 1. An unprepared student makes random guesses for the 10 true-false questions on a pop quiz. Find the probability that there is at least once correct answer. 2. A box contains four red, three blue, and six g

Statistics and Probability

Hello. Can anybody help me with these 6 example questions that were created. I want to use them as a study guide. 1. 45 Human Resource major students and 25 Culinary Arts major students had arrived. What is the empirical probability that the next student to come will be a Human Resource Major? 2. A box contains four red

Probability Computations for SImulation Tables

The time between arrivals of customers to a gas station pump is given by the following probability distribution time between arivals (min) probability 1 0.1 2 0.2 3 0.5 4 0.2 The time required by a customer is given by the following probability distri

Probability: Social Security Numbers

Can anybody help me with this two examples problems. Some of them are giving me a lot of numbers which it should give me a few numbers comparing them to the other results I was manage to do. ------------------------------------------------------------------------------------- 2. Social Security Numbers Each social security n

Probability Owner Computers

1. Letter and Digit. A new computer owner creates a password consisting of two characters. She randomly selects a letter of the alphabet for the first character and a digit (0,1,2,3,4,5,6,7,8,9) for the second character. What is the probability that her password is "k9"? Would this password be effective as a deterrent against so

Sample Probability

I need help towards doing this example. Men Women Boys Girls Survive 332 318 29 27 Died 1360 104 35 18 If one of the Titanic passengers is randomly selected, find the probability of getting a woman or someone who did not survived the sinking.

Distribution Theory.

Determine the distribution of Y = X_1 + X_2 + . . . + X_n by first determining the joint distribution of Z_1 = X_1 Z_2 = X_1 + X_2 Z_3 = X_1 + X_2 + X_3 . . . Z_n = X_1 + X_2 + X_3 + . . . + X_n and then computing the marginal distribution of Z_n According to my text book: Exp(a), a>0 has density

Probability: Binomial approximation to normal distribution

In a large university, 30% of the incoming first-year students elect to enroll in a personal finance course offered by the university. Find the probability that of 800 randomly selected incoming first-year students, at least 260 have elected to enroll in the course. Thanks.

Probability puzzle

A prison has 20 balls, 10 black and 10 white. The prisoner is to arrange the balls in 2 boxes. All of the balls must be used and there must be at least one ball in each box. An executioner will select one box at random and then one ball at random from the chosen box. The prisoner is set free if the ball is white and executed if

Conditional Probability: The Probability of Carrying a Disease

Question: A common test for AIDS is called to ELISA (enzyme-linked immunosorbent assay) test. Among 1 million people who are given the ELISA test, we can expect results similar to those given in the attached table. Please view the attachment for the rest of the question.

Conditional Probability Problem

Please help with the following probability problem. You are a member of a class of 18 students. A bowl contains 18 chips: 1 blue and 17 red. Each student is to take 1 chip from the bowl without replacement. The student who draws the blue chip is guaranteed an A for the course. (a) If you have a choice of drawing first, fi

Conditional Probability: Ball Colour

An urn contains four coloured balls: two orange and two blue. Two balls are selected at random without replacement, and you are told that at least one of them is orange. What is the probability that the other ball is orange?

Some Questions on Bayes Theorem (Conditional Probability)

Some questions on Bayes Theorem. Let A1 and A2 be the events that a person is lef-eye dominant or right-eye dominant......This should give you a good idea about the question. You may also look at the question in the attached file.

Probability and Combinations for Baseball World Series

The world series in baseball continues until either the American League team or the National League team wins four games. How many different orders are possible (e.g; ANNAAA means the American League team wins in six games) if the series goes (a) Four games? (b) Five games? (c) Six games? (d) Seven games?

Normal probability calculation ,

The average amount customers at a certain grocery store spend yearly is $636.55. Assume the variable is normally distributed. If the standard deviation is $89.46, find the probability that a randomly selected customer spends between $550.67 and $836.94.

Probability and Widgets

A factory has two machines that make widgets. The main machine, named Pacific makes 75% of all the widgest daily. It is known that 1% of the widgets made by Pacific are defective. However, 2% of the widgets made by the second machine named Atlantic, are defective a. what is the probability taht a widget produced by the factor

Probability and the Binomial Distribution

A manufacturing company has 10 machines in continous operation during a workday. The probability that an individual machine will break down during the day is .10. Determine the probability that during any given day 3 machines will break down.


A box contains five blue, eight green, and three yellow marbles. If a marble is selected at random, what is the probability that it is yellow?

Statistics: Solving a binomial distribution problem

Historical data shows 15% of the customers entering a store make a purchase. There are 50 customers in the store at the moment. The store manager wants to know what is the probability that 25 or more of them will make a purchase in order to determine whether he will need to add additional staff to the shift.

Ace Computer store probability

Ace Computer store receive laptops from 3 different computer vendors. Ace receive 20% of laptop, from B 40% and 40 % from vendor C. The probability of receiving a defective laptop from A is .01, B, .02 and C, .08. a. Develop a probability tree showing all marginal, conditional and joint probabilities. b. Develop a joint tabl

Probability Distribution: Skittles Example

1. A small bag of Skittles candies has the following assortment: red (12), blue (5), orange (15), brown (0), green (16), and yellow (7). Construct the probability distribution for x. X is color; so the p(green) = 16/n, where n is the total count, and so on... 2. Find the mean and standard deviation of the following probabilit

Probabilities and Normal Distributions

Part I T/F & Multiple Choice 1. The sum of all probabilities in any discrete probability distribution is not always exactly one, since some of the probabilities may be slightly larger than one. ___ T/F 2. In any binomial probability experiment, independent trials mean that the result of one trial does not affect the prob

Decision Making and Probability

1. The probability of an event a. is the sum of the probabilities of the sample points in the event. b. is the product of the probabilities of the sample points in the event. c. is the maximum of the probabilities of the sample points in the event. d. is the minimum of the probabilities of the sample points in the event.

Random Variables, Probability Distributions, Normal and Binomial Distributions

Please see the attached file for the fully formatted problems. 1. Explain the difference between a discrete and a continuous random variable. Give two examples of each type of random variable. 2. Determine whether each of the distributions given below represents a probability distribution. Justify your answer. a

Data and Probability

1. How many variations in first-, second-, and third-place finishes are possible in a 100-yd dash with 6 runners? 2. In a Chinese restaurant, the menu lists 8 items in Column A and 6 items in column B. To order a dinner, the diner is told to select 3 items from column A and 2 from column B. How many dinners are possible?

Mean, Median, Mode and Z-Scores

Week 4 Quiz (covering Chapters 8 - Counting Principles; Further probability Topics and 9 - Statistics) Submit in your Individual forum by Monday. Show your work (Show the formula, the values of the variables in the formula, and the result of the formula.). 1. How many variations in first-, second-, and third-place fini

Probability and Expected Value

Questions - u12 The questions are to be answered with full solutions. Be sure to focus on proper mathematical form, including: 1. One equal sign per line, 2. Equal signs in each question lined up vertically with each other, 3. No self-developed short form notations, 4. One step or idea per line, 5. Show complete solut