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Statistics: test mean reaction time of female candidates for flight school

In a standard test for reaction time, female candidates for flight school are found to have times that are normally distributed with a mean of 0.65 seconds and a standard deviation of 0.15 seconds. If one candidate is randomly selected, find the probability that her reaction time is below the maximum allowable time of 1.00se

Statistics: Poisson distribution

In the example: P(x; &#956;) = (e-&#956;) (&#956;x) / x! P(3; 2) = (2.71828-2) (23) / 3! P(3; 2) = (0.13534) (8) / 6 P(3; 2) = 0.180 Where 3! = 6, how was that number calculated? In the example: P(x < 3, 5) = P(0; 5) + P(1; 5) + P(2; 5) + P(3; 5) P(x < 3, 5) = [ (e-5)(50) / 0! ] + [ (e-5)(51) / 1! ] + [ (e-5)(52) /

Statistic Problems and Descriptive Question

I managed to do all my other questions but I cannot figure these specific problems out. They are not fully explained in the book and I cannot figure it out by searching for help online. I have worked all day yesterday and most of today on this and just cannot get these specific problems! If you could explain how to do them with

ANOVA and Regression Calculations

Case Study of ZYX Incorporated Case Study of ZYX Incorporated Executive Summary The below details is a summary of the research and findings that was completed by Team B Enterprises. This study was conducted with the employees to determine the job satisfaction and stress level of the recently announced move to a new locat


I NEED THEM BACK WITHIN 1 HR FROM NOW.SEE DATAS CAREFULLY. 1.According to Investment Digest (&quot;Diversification and the Risk/Reward Relationship&quot;, Winter 1994, 1-3), the mean of the annual return for common stocks from 1926 to 1992 was 15.4%, and the standard deviation of the annual return was 24.5%; During the same

Quantitative Analysis for Management (10th ed.)

From historical data, Harry's Car Wash estimates that dirty cars arrive at the rate of 10 per hour all day Saturday. With a crew working the wash line, Harry figures that cars can be cleaned at the rate of one every 5 minutes. One car at a time is cleaned in this example of a single-channel waiting line. Assuming Poisson arriva

Normal Probability: Life span of bulbs & Cut off mark..

1). In an examination the mean score was 80, the standard deviation was 10, and the grades followed a normal distribution. The instructor wants to assign A's to the top 12%. Where should the cutoff point for A's be? (2). A company manufactures electric light bulbs that have an average life of 1000 hours and a standard deviati

Probability of Argentina consumer selections

Based on the table given in the attached file: 1. What is the probability that a consumer selected at random purchased fewer products than before? Round to 4 decimal places. 2. What is the probability that a consumer selected at random purchased the same number or more products than before? Round to 4 decimal places. 3

Statistics problem

I need help with these specific questions on my homework. I did the rest but can't figure these out. Please include an explanation because I don't want to get behind by not understanding how to solve these questions. I'm already struggling enough - don't need to add more to it. 1. A distribution has a standard deviation of

Statistics: Five Random Variable problems

Learning objectives: distinguish between discrete and continuous random variable; compute statistics about random variable; compute statistics about a function of a random variable; compute statistics about the sum of a linear composite of random variables; identify which type of distribution a given random variable is most like

Probability - Random Samples

According to the U.S. Census Bureau, the mean household income in the United States in 2000 was $57,045 and the median household income was $42,148 (U.S. Census Bureau, "Money Income in the United States: 2000,", September 2001). The variability of household income is quite large, with the 10th percentile approxi


1. There is a 20% probability of rain tomorrow means that: a. Tomorrow it will be raining during 0.2 of the day, and the rest of the day it will be clear. b. Out of the next 5 days, one day it will be raining. c. According to the records, if a weather like one we have today occurred in the past, then 20% of cases it w

Statistics: 4 problems about random variables and their probability distributions

3-44 A real estate agent has four houses to sell before the end of the month by contacting prospective customers one by one. Each costumer has an independent 0.24 probability of buying a house on being contacted by the agent. a) If the agent has enough time to contact only 15 customers, how confident can she be of selling a

Home sales and interest rates

The probability that home sales will increase in the next 6 months is 0.25. The probability that the interest rates on loans will go up in the same period is estimated to be 0.74. The probability that home sales or interest rates will go up during the next 6 months is estimated to be 0.89. The probability that both home sales an

Statistics M2: Six comprehensive problems

1. An auto supply store uses a fixed order size with safety stock system to control the inventory of a type of motor oil it sells. Demand for the oil averages 20 units per day (7300 units per year) and the standard deviation of the daily demand is 4.3 units. For this item, the cost of placing each order is $35. The store purchas

Statistics: Union and intersection problems

1) Let G be the event that a girl is born. Let F be the event that a baby over 5 pounds is born. Characterized the union and the intersection of the two events? 2) Consider the event that a player scores a point in a game against team A and the event that the same player scores a point in a game against team B. What is the u

Statistics: Tchebychev inequality for samples

The Tchebychev inequality can also be stated in the following way: For any random variable x with mean equal to &#956; and variance equal to &#948;². The minimum probability of X belong to the interval X?[ &#956;-k, &#956;+k] is at least: P( | X- &#956;|<k &#8805; 1-( &#948;/k²) Suppose that the random variables x1, x2, x

Poisson distribution probabilities and recursion relationship

The Poisson distribution is given by the following P(x,λ)=e ^ -λ * λ^x! x=0,1,2,3.....j..... Where λ>0 is a parameter which is the average value &#956; in poisson distribution. a) show that the maximum poisson probability P(x=j,λ) occurs at approximately the average value, that is λ=j if λ>1. (hint: you can take t

Statistics: Simulate the emergency calls for 3 days, using a random number table.

Simulate the emergency calls for 3 days, using a random number table. Compute the average time between calls and compare this value with the expected value of the time between calls from tthe probability distribution. Rescue receives an emergency call every 1, 2, 3, 4, 5, or 6 hours, according to the following probability di