Statistical Analysis in Social Sciences and Business

Probability Calculation with Defective Items

A sample of 4 calculators was extracted from a total order, of which 36 are defective and 28 are not. What is the probability that the four selected calculators are defective?

a) 0.1001

Hypothesis Testing: Americans Sharing Homework Responsibilities

An article in a sociology journal states that at least 66% of Americans share responsibility with their spouses to monitor their children’s homework. In a city in California, a study was conducted involving a

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Essential Formulas and Theorems in Multivariable Calculus and Differential Equations

Convergence of Sequences

Convergence Point

To resolve the limit:

Uniform Convergence

  • State the Supremum Criterion:

To check for uniform convergence, the characterization of the supremum criterion is used, which states that converges uniformly to in M if and only if:

  • Calculate

  • Calculate the maximum (supremum) that can be reached by the absolute value in the interval marked by
  • Check that the supremum tends to zero as

Power Series

Series of the form:

Convergence Study

  • Calculate the radius of convergence:

If

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Understanding Company Assets, Liabilities, and Accounting

The assets and means that a company uses to perform its activity, i.e. to operate, are the heritage of the company.

If we consider the value of each of the elements of heritage and add them, we will have a number that represents the value of heritage.

  • The goods are the material means necessary for the company’s business: buildings, machines, money.
  • The rights are those effects that the company can claim: sales invoices unpaid by customers, etc.
  • The obligations are the debts that the company has with
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Probability and Combinatorics: Key Concepts and Examples

Probability and Combinatorics: Key Concepts

Combinatorics provides procedures and formulas necessary to count the possibilities to choose a set of items with certain characteristics.

Permutations and Variations

  • By taking all elements of a finite set and ordering them in all possible ways, we have a permutation.
  • A variation of order k (or k-order variation) is a group of k elements chosen from a total set, where each group is different either by the elements it contains or by the order in which they
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Stock Return Analysis and Statistical Concepts

Stock Comparison: Return and Risk

Stock 1: = 9.62% and s = 23.58%

Stock 2: = 12.38% and s = 15.45%

represents the average return of a stock.

Stock 2 has a higher average return because its (12.38%) is greater than Stock 1’s (9.62%).

Stock 1 is riskier. Standard deviation (s) measures return volatility. A higher standard deviation indicates wider fluctuations and greater unpredictability. Therefore, Stock 1 is riskier (s = 23.58%) than Stock 2 (s = 15.45%).

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Implication: Sharpe Ratio

Stock

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Number Sense, Measurement, and Geometry in Early Childhood

Building Number Sense in Early Childhood

Stages of Number Development

Third Stage: Cardinality Rule

  • Children aged 5 to 10 can recognize that the last number counted represents the total (cardinality) of the set.
  • They do not connect the order of counting to the relative size of numbers.
  • Children do exercises with numbers 1 to 9.
  • They identify characteristics and qualities of the set to be counted. If sorting, they understand the desired size and can represent it in words or pictures.

Fourth Stage: Relative

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