Purchase Solution

Distribution of Sample Mean - Linkages

Not what you're looking for?

Ask Custom Question

Please see the attached file.

Three shafts are made and assembled in a linkage. The length of each shaft, in centimeters, is distributed as follows:

Shaft 1: l_1 ~ N(75,0.09)
Shaft 2: l_2 ~ N(60,0.16)
Shaft 3: l_3 ~ N(25,0.25)

The length of the linkage is calculated by l = l_1 + l_2 + l_3. Assume the shafts' length are independent to each other:

a) What is the distribution of sample mean l?

b) How can we define the boundaries such that P(1 <= b_1 or 1 >= b_2) = 0.00270?

c) Assume that under abnormal production condition, the mean length of shaft l changes to 80 with the variance unchanged, and distribution parameters of the other two shafts are not changed. Suppose a sample of size n (n = 25) linkage is randomly selected from the abnormal production condition, what is the distribution of the new sample mean, Xbar?

d) Suppose the two boundaries, b_1 and b_2, are still used, find P(b_1 <= Xbar <= b_2)?

Attachments
Purchase this Solution

Solution Summary

The distribution of a sample mean of three shafts made in an assembled linage is determined.

Purchase this Solution


Free BrainMass Quizzes
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.

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.

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.