Purchase Solution

Happy Valley Machine Works Company

Not what you're looking for?

Ask Custom Question

1. The Happy Valley Machine Works Company loses a shipment of its machines due to an error by one of its three executives (Harry, Sam and Mabel), but it cannot tell with certainty which executive was responsible for the error. On the basis of past performance, it is known that the probability that Harry would make such a mistake (given that he were responsible for the shipment) is 0.05, the probability that Sam would do so is 0.15 and that Mabel would do so is 0.10. If Harry is responsible for 50% of all shipments and the rest are split evenly between Mabel and Sam, what is the probability that Sam is responsible for the lost shipment?

3. For their market research project, Sam and Mary are surveying firms in their area. They ask each firm how many of their workers carpool and how many are at least 40 years old. They have received the following information about 75 coworkers

20 of the car-poolers are at least forty years old
15 of the car-poolers are younger than forty
35 of the workers are at least forty years old
25 of the workers who do not carpool are less than forty

a) Construct the probability matrix for this data
b) What is the probability that a worker chosen at random who does not carpool is at least 40 years old?
Explain whether a worker's age and her carpooling status are statistically independent.

Purchase this Solution

Solution Summary

This solution contains over 500 words and calculations to aid you in understanding how to solve these problems.

Solution provided by:
Education
  • BSc , Wuhan Univ. China
  • MA, Shandong Univ.
Recent Feedback
  • "Your solution, looks excellent. I recognize things from previous chapters. I have seen the standard deviation formula you used to get 5.154. I do understand the Central Limit Theorem needs the sample size (n) to be greater than 30, we have 100. I do understand the sample mean(s) of the population will follow a normal distribution, and that CLT states the sample mean of population is the population (mean), we have 143.74. But when and WHY do we use the standard deviation formula where you got 5.154. WHEN & Why use standard deviation of the sample mean. I don't understand, why don't we simply use the "100" I understand that standard deviation is the square root of variance. I do understand that the variance is the square of the differences of each sample data value minus the mean. But somehow, why not use 100, why use standard deviation of sample mean? Please help explain."
  • "excellent work"
  • "Thank you so much for all of your help!!! I will be posting another assignment. Please let me know (once posted), if the credits I'm offering is enough or you ! Thanks again!"
  • "Thank you"
  • "Thank you very much for your valuable time and assistance!"
Purchase this Solution


Free BrainMass Quizzes
Measures of Central Tendency

Tests knowledge of the three main measures of central tendency, including some simple calculation questions.

Terms and Definitions for Statistics

This quiz covers basic terms and definitions of statistics.

Know Your Statistical Concepts

Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.

Measures of Central Tendency

This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.