Purchase Solution

Example of calculation of the mean value and variance

Not what you're looking for?

Ask Custom Question

The service life of an incandescent light bulbs used domestically was
investigated.
It was found that a light bulb can last up to 3 years, and the probability
distribution of the number of years a light bulb was used before failure is given
below:
Years light bulb was used before failure (x) 0 1 2 3
Probability of x years 0.1 0.3 0.5 0.1

(i) What is the mean service life of a light bulb?
(ii) What is the variance and standard deviation of a service life of a light
bulb?

Attachments
Purchase this Solution
Solution Summary

This is a simple problem showing how to calculate variance and mean value (average) in a probability problem.

Purchase this Solution
Free BrainMass Quizzes
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.

Terms and Definitions for Statistics

This quiz covers basic terms and definitions of statistics.

Measures of Central Tendency

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

View More Free Quizzes
Related BrainMass Solutions

  • Constructing a probability distribution using a frequency distribution

    Then find the mean, variance and standard deviation.

  • Independent sample t test

    Formula for the calculation and Interpretations of the results are also included.

  • Mean and variance of discrete random variable

    Suppose that a variable x has the following distribution function: x p(x) 3 0.23 5 0.41 9 0.36 What is the expected value of (X - mean of x)^2? Please see attached file. Calculation of mean and variance of a discrete random variable.

  • Test of hypothesis using ANOVA

    2 not equal to M 3 (The means are not the same) mean crash damages are not the same for these three vehicles 2) Calculation of Mean Square (Treatment) or MS(T) MS(T)=SS(T)/degrees of freedom= Variance among the sample

  • Test Statistic: Two sample Z test for Mean

    As part of this trial, they wish to determine whether there is a difference between the effectiveness for women and for men. At a= 0.05 what is the test value?

  • Pooled Variance, Interval Data and Hypothesis Testing

    318958 Pooled Variance, Interval Data and Hypothesis Testing 1. What is pooled variance and why is it important? 2. Explain what interval data is and give an example: 3.

  • Pooled variance, Interval data & Hypothesis Testing

    326891 10 Statistics problems: Pooled variance, interval data, t-test, unpaired data, z-test 1. What is pooled variance and why is it important? 2. Explain what interval data is and give an example: 3.

  • ANOVA for LLD Records Problem

    ____ Please see the attachments The solution provides step by step method for the calculation of ANOVA, mean squares and the common population variance.

  • Descriptive Statistics

    . = = 1.858640755 The solution provides step by step method for the calculation of mean, median, mode, range, sample variance and sample standard deviation. Formula for the calculation and Interpretations of the results are also included.

View More Related Solutions