/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 37 The following table lists five p... [FREE SOLUTION] | 91Ó°ÊÓ

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The following table lists five pairs of \(m\) and \(f\) values. $$ \begin{array}{c|ccccc} \hline m & 5 & 10 & 17 & 20 & 25 \\ \hline f & 12 & 8 & 6 & 16 & 4 \\ \hline \end{array} $$ Compute the value of each of the following: a. \(\Sigma m\) b. \(\Sigma f^{2}\) c. \(\Sigma m f\) d. \(\Sigma m^{2} f\)

Short Answer

Expert verified
The solutions are: a. \(\Sigma m = 77\), b. \(\Sigma f^{2} = 516\), c. \(\Sigma mf = 662\), d. \(\Sigma m^{2}f = 11734\).

Step by step solution

01

Calculate \(\Sigma m\)

This symbol \( \Sigma m \) denotes the sum of all \( m \) values in the table. Add together the \( m \) values: \(5 + 10 + 17 + 20 + 25 = 77\).
02

Calculate \(\Sigma f^{2}\)

The symbol \( \Sigma f^{2} \) means the sum of the squares of all \( f \) values. Square each \( f \) value, then add them together: \(12^2 + 8^2 + 6^2 + 16^2 + 4^2 = 144 + 64 + 36 + 256 + 16 = 516\).
03

Calculate \(\Sigma mf\)

The symbol \( \Sigma mf \) means the sum of the product of each pair of \( m \) and \( f \) values. Multiply each pair, then add them together: \(5*12 + 10*8 + 17*6 + 20*16 + 25*4 = 60 + 80 + 102 + 320 + 100 = 662\).
04

Calculate \(\Sigma m^{2}f\)

The symbol \( \Sigma m^{2}f \) represents the sum of the products of the square of each \( m \) value and its corresponding \( f \) value. Square each \( m \) value, then multiply by the corresponding \( f \) value, then add them all up: \(5^2*12 + 10^2*8 + 17^2*6 + 20^2*16 + 25^2*4 = 300 + 800 + 1734 + 6400 + 2500 = 11734\).

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Statistical Computation
Statistical computation involves using mathematical operations to summarize and analyze data sets. It often uses summation notation, represented by the Greek letter \( \Sigma \), to indicate the sum of a sequence of numbers. This notation provides a compact and efficient way to present long sums.
In the original exercise, various statistical computations like \( \Sigma m \), \( \Sigma f^2 \), \( \Sigma mf \), and \( \Sigma m^2f \) are used to extract meaningful insights from the given data. Understanding these computations is crucial for interpreting data in fields like economics, biology, and social sciences.
  • \( \Sigma m \) summarizes the total values of \( m \).
  • \( \Sigma f^2 \) captures the variation among \( f \) values.
  • \( \Sigma mf \) and \( \Sigma m^2f \) involve multiplications that uncover relationships between \( m \) and \( f \).
These computations help in providing a clear, organized structure for data analysis.
Sum of Squares
The sum of squares is a foundational concept in statistics, measuring the variation or dispersion of a set of data points. It is particularly useful for determining the variability of a dataset.
In the exercise, \( \Sigma f^2 \) is calculated by squaring each element of \( f \), and then adding these squares together. This yields a value that represents the total variability among the \( f \) values.
The formula is given by:
  • Square each individual \( f \) value: \( f_1^2 \), \( f_2^2 \), ..., \( f_n^2 \).
  • Add them together: \( \Sigma f^2 = f_1^2 + f_2^2 + \ldots + f_n^2 \).
Understanding the sum of squares is crucial when interpreting data variability, enabling further analysis such as standard deviation and variance calculations.
Product of Pairs
The product of pairs in statistical computation is used to explore relationships between two sets of data. In the exercise, this involves multiplying two corresponding values from different data sets, namely \( m \) and \( f \), and then summing the results.
This is represented as \( \Sigma mf \) and provides insight into the concurrent variability of the two datasets. Such products can reveal important correlations that help in understanding how changes in one variable might affect another.
To compute this, follow these steps:
  • Multiply each pair: \( m_1f_1, m_2f_2, \ldots, m_nf_n \).
  • Sum these products: \( \Sigma mf = m_1f_1 + m_2f_2 + \ldots + m_nf_n \).
This operation is frequently used in regression analysis, where the interplay between variables helps to create predictive models.
Data Analysis
Data analysis is interpreting numerical data to make informed decisions. The computations in the exercise, such as \( \Sigma m^2f \), illustrate deeper analytical methods used to understand complex relationships among variables.
In this specific calculation, each \( m \) value is squared, then multiplied by its corresponding \( f \) value. Summing these results provides a value that can highlight more complex interactions, often used in advanced statistical modeling.
Here’s how you calculate \( \Sigma m^2f \):
  • Square each \( m \) value: \( m_1^2, m_2^2, \ldots, m_n^2 \).
  • Multiply by corresponding \( f \) values: \( m_1^2f_1, m_2^2f_2, \ldots, m_n^2f_n \).
  • Sum these products: \( \Sigma m^2f = m_1^2f_1 + m_2^2f_2 + \ldots + m_n^2f_n \).
Data analysis by such computations provides insights into hidden patterns and relationships, essential for strategic planning and decision-making in various fields.

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