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Probability

Normal Probability: Expected Scores

A test has a mean of 30, a standard deviation of 6, and scores that are normally distributed. Of the 50 people who took the test, about how many people would be expected to score between 24 and 36? A. 25 people B. 34 people C. 47 people D. There is not enough information to tell

Probability: Number of possible access codes

P(E)= number of outcomes in event E _________________________ total # of outcome in sample space The access code for a garage door consists of three digits, each digit can be 2 through 9 and each digit can be repeated 1. Find the number of possible access codes? = 8x8x8= 512 2. The probability of rand

Statistics: Sketch distribution for City of Nashville's recycling program

The city of Nashville determined in 2009 that the population mean weight of municipal solid waste (MSW) generated per person per day was 6.40 lbs with a population standard deviation of 1.44 lbs. Assume a normal distribution. With the objective of promoting recycling of MSW and of reducing the costs of landfill disposal, the Nas

Find expected profit of sales distributions for skim milk gallons

If you purchase 5 gallons of skim milk for $2 per gallon and sell it for $3 per gallon and receive a refund for unsold milk of $1 per gallon. y = Profit = NoSold(PriceSell-PriceRefund) + NoPurchased*(PriceRefund-PriceYouPurchasedFor) What is the expected profit or loss for the following distribution of sales? x 0

Probability

A study of college football games shows that the number of holding penalties assessed has a mean of 2.2 penalties per game and a standard deviation of 0.8 penalties per game. What is the probability that, for a sample of 40 college games to be played next week, the mean number of holding penalties will be 2.05 penalties per game

Probabilities: Standard Normal or Z Score

The Modulus of rupture (MOR) for a particular grade of pencil lead is known to be 6500 psi with a standard deviation of 250 psi. a. Find the probability that a random sample of 16 pencil leads will have an average MOR between 6400 and 6550 psi. b. What did you assume in order to find this probability?

Standard Normal or Z score for finding the probability

Yashchin (1995) discusses a process for the chemical etching of sillicon wafer used in integrated circuits. This process etches the layer of silicon dioxide until the layer of mental beneath is reached. This company moniters the thickness of the silicon oxide layer because thicker layers require longer etching times. Historicall

Statistics terms: Trial, outcome, success, independent, probability, logic

1. Statisticians use terms like trial, outcome and success in a particular way in reference to probability. What do each of these three terms mean in this context? 2. How is the term independent used by Statisticians? 3. On a game show, eight people have won the grand prize and a total of 266 people have completed. Es

Compute mean profit where x is a random number

Profit = m(x) = 500x^2 Where x is a random number with probability frequency of: f(x) = 2(1-x) 0 < x < 1 0 elsewhere Compute the mean profit: The answer is $83.33, but I am unclear about how to arrive at that answer.

Difference in wording of a percentage questions for Pentax users

I don't understand what the difference in the wording is asking for between these three questions on percentages. To me it appears that two are asking the same question. Please answer the questions and explain how the wording differentiates what is being asked. Female Male Total Sony Cyber Shot 73 59 132 Koda

Bionominal Probability for a Tamiami shearing machine: defective pieces

A Tamiami shearing machine is producing 10 percent defective pieces, which is abnormally high. The quality control engineer has been checking the output by almost continuous sampling since the abnormal condition began. What is the probability that in a sample of 10 pieces: Exactly 5 will be defective? 5 or more will be defec

Legitimate continuous probability distribution

Assuming that the function below is a legitimate continuous probability distribution, find: P(X > 200) Hint: let u = x+100 (substitution rule) f(x) = 20000 / (x +100)^3 x > 0 0 elsewhere

Probability of nonconforming apple juice containers on Machine I and II

A well known apple juice production company maintains records concerning the number of unacceptable containers of apple juice obtained from the filling and capping machines. Based on past data, the probability that a container came from machine I and was nonconforming is 0.03 and the probability that a container came from machi

Probability Problem: Horse race with 12 entries

A horse race has 12 entries. Assuming that there are no ties, what is the probability that the three horses owned by one person finish first, second, and third? The answer in my book is .0045. Please show the workings.

True or False Probability questions.

1. (True or False) The six letters in the word CHEESE are rearranged in a random manner. The probability that it will still spell CHEESE is less than .5. 2. (True or False) In bridge(card game), it is more likely that North has no spades than that he has no aces. 3. (True or False) If three distinguishable balls are distri

Probability of patient surviving from disease

1. The probability that a patient recovers from a disease is 63%. What is the probability that: A) 2 out of 3 patients in a group with the disease will survive? B) Probability that all 3 will survive? Answers: Just show me how to get there. A) 44.1% B) 25% 2. There are 3 consulting firms that have the following

Example Statistics Problems

1. A study of a court system produced the following results: Note: G= guilty , G' = not guilty , J= judged guilty , J'= judged not guilty 80% of guilty (G) judged guilty (J) 93% of innocent (G') judged innocent (J') 5% innocent (G') judged guilty (J) 77% guilty (G) A) Find probability judged guilty (means find P(J

Find the standard deviation of the distribution

A marketing poll revealed that 45% of Americans say they that they have dinner regularly as a family. You randomly choose 10 American families and ask if they regularly have dinner together as a family. 1. Does this situation meet the binomial requirements? Why or why not? Address the four characteristics in the Key Points.

Two-thirds of US households purchased ground coffee: annual expenditures

In recent years, about two-thirds of US house holds purchased ground coffee. Consider the annual ground coffee expenditures for households purchasing ground coffee. assuming that these expenditures are approximately distributed as a normal random variable with a mean of $65.16 and a standard deviation of $10.00 A. find the pr

Probability of Sample Proportion

Cashier records from the last year show that 60% of all Grayson's Grocery store customers use a previously-obtained Grayson's discount card upon checkout. Management suspects the percentage of actual cardholders is higher because some customers may not use their Grayson's card during every visit They decide to sample random cust

Sampling Distributions of diameter widths of steel rebar

The population of diameter widths of steel rebar is normally distributed with a mean of 2.5cm and a standard deviation of 0.25cm. What is the probability that the average diameter width of a strip of rebar from a sample of 23 strips is more than 2.6cm wide?

Employees who carry secondary health insurance

Suppose that a large corporation surveys all of their employees, and finds that 24% of them carry secondary health insurance. A representative from GoldStar Care visits 100 employees, in hopes of selling about 76% of them secondary health insurance. Find the probability that at least 27 of them already carry secondary health ins