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Statistics: normally and binomially distributed random variables

1) A videotape store has an average weekly gross of $1,158 with a standard deviation of $120. Assuming this to be a normally distributed random variable, calculate the following: a. Probability the weekly gross will exceed $1,261. b. Proportion of weeks the weekly gross is less than $1,080. c. Probability the weekly gross is

Statistics problem

1) A survey revealed that 21.5% of the households had no checking account, 66.9% had regular checking accounts, and 11.6% had NOW accounts. Of those households with no checking account 40% had savings accounts. Of the households with regular checking accounts 71.6% had a savings account. Of the households with NOW accounts 7


Because of a recent incident in which a number of people became ill after eating undercooked hamburger meat, intensive interest has centered around the cooking time for hamburger patties. In the past, the cooking time at a local fast food firm has been found to be uniformly distributed between 4 and 5 minutes. a) A TV report

Find the probability of an event.

1.The Census Bureau reports that 55% of all 3-to-5-year-old children attended preschool programs at least a portion of the day. If 18 children are chosen at random, what is the probability that fewer than six children attend such a program? 2. Experimenters in ecology found that the average density of zooplankton in a pond w

Probability distribution

702) On any given day the number of leasable square feet of office space available in a small city is a normally distributed random variable within mean of 850,000 square feet and a standard deviation of 25,000 square feet. The number of leasable square feet available in another city is normally distributed with a mean of

Statistics and Probability

A retail grocer has decided to market organic "health food" and will purchase a new line of products from each of two suppliers. Unknown to the grocer, the two suppliers are in financial distress. Past experience has shown that, for firms with similar credit histories, the probability that bankruptcy will be initiated one year

Statistics Problem

Please help me with the following problem: The city of a particular community consists of five elected residents of the community, two of whom are land developers. The city mayor plans to elect two members at random from the council to study and make recommendations on land use rezoning requests. The composition of this su


In a game at a fraternity party, there are 10 bottles to knock down. Five fraternity brothers line up to shoot the bottles down, each a perfect shot. Each brother selects one bottle at random and shoots. Find the e-value of your distribution of the number of bottles knocked down. Each brother is a perfect shot so the probabi


X follows a normal distribution with mean 20 and standrad deviation 4. Find b such that Prob(-b<=X-20<=b)=0.95

E-value of a distribution: coin flips

Bill flips a coin that can land heads or tails, and you assign equal probabilities to each, with all flips mutually irrelevant. Bill will flip the coin until he sees a consecutive sequence of tails, tails, tails. What is the e-value of your distribution of the number of flips until this happens? For example, if Bill flips HHT

Probability of Rolling of the Die

A person rolls a pair of six-sided dice, which are equally likely to come up any number from 1 to 6. If the person rolls a seven he gets $0. If he rolls any other number, he can choose either to win that amount or play the game again from the start. This person believes that the best strategy is to keep rolling until he gets a "

Working with probability in the given situation given x-bar and sample size.

Your troop's past cookie sales went sour last year. Parents had to bail you and your troop member out of the hole. For next year the troop wants to know from your customers the planned cookie orders are likely to be for the next year. You get x-bar = $160,000 s = $80,000 and n = 1000. What is the probability that the r

Statistic - Number of ways to select an object

3) Furnish 2 offices each with a desk, chair, and file cabinet and 2 bookcases. At a local store there are 6 models of desks, 8 models of chairs 4 models of file cabinets and 10 models of bookcases. How many choices do you have if you want to select two desks, two chairs, two file cabinets and four bookcases if you don't want t


1. Find the value of (a) in the following discrete probability distribution: X -2 0 2 P(x): a 0.35 0.25 2. A binomial distribution is based on n=25 and p=0.1. Find the probability that x =1. 3 A production process produces parts with weights that are normally distributed with a mean of 1.75 ounces and a standard devi

Working with sampling distribution and probability.

A southern state has an unemployment rate of 6%. The state conducts monthly surveys in order to track the unemployment rate. In a recent month, a random sample of 700 people showed that 35 were unemployed. a) If the true unemployment rate is 6%, describe the sampling distribution of p^. b) Find P(p^ >= 0.05) c) Assum


1.Find the probabilities for the standard normal random variable z: P(-1.55<z<.44) 2. Find zo such that P(-zo<z<zo)=.99 3. A normal random variable x has mean =1.20 and standard deviation =.15. Find the probability of the x value. 1.35<x<1.50 b. x>1.38 4. Assume the heights of men have a mean of 69 inches with a stan


26. MCQ: A family center conducted research on carbohydrate consumption in the high school and found that 30% of all high school sophomores ate at least four candy bars a day. If 20 high school sophomores are selected at random, what is the probability that exactly 6 of these eat at least 4 candy bars a day? a) 0.300 b)

Statistics: geological study and large elevator

1. A geological study indicates that wells drilled in a certain area should strike water with probability 0.2. Find the probability that: a) first strike of water comes in the 3rd well drilled b) 3 strikes of water in 5 drills 2. A large elevator has a max weight limit of 10,000 lbs. Suppose a load has 45 boxes. This has a

Probability using Binomial Distribution

7) On a very hot summer day, 5% of the production employees at Midland States Steelare absent from work. The production employees are to be selected at random for a special in-depth study on absenteeism.What is the probability of selecting 10 production employee at random on a hot summer day and finding that none of them are abs

Working with combinations.

I have 9 chalkboards to be distributed amongst 4 classrooms. If each class must get at least 1 chalkboard, how many possible divisions can I have?

Binomial Probability

A factory employs several thousand workers, of whom 30% are Hispanic. If the 15 members of the union executive committee were chosen from the workers at random, the number of Hispanics on the committee would have the binomial distribution with n=15 and p=0.3 a)What is the probability that exactly 3 members of the committee are

Working with binomial probability.

If the parents have 5 children, the number who have type O blood is a random variable X that has the binomial distribution with n=5 and p=0.25 a) What are the possible values of X? b) Find the probability of each value of X. Draw a histogram to display this distribution. (Because probabilities are long-run proportions, a hi