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For the following numerical variables, state whether each is discrete or continuous. a. The length of a l-year-old rattlesnake b. The altitude of a location in California selected randomly by throwing a dart at a map of the state c. The distance from the left edge at which a 12 -inch plastic ruler snaps when bent sufficiently to break d. The price per gallon paid by the next customer to buy gas at a particular station

Short Answer

Expert verified
a. Continuous, b. Continuous, c. Continuous, d. Discrete

Step by step solution

01

Identify the type of variable for the length of a rattlesnake

The length of a 1-year-old rattlesnake is a continuous variable because it can take any value within a certain range. The length can be any nonnegative real number.
02

Identify the type of variable for the altitude of a location in California

The altitude of a location in California selected randomly by throwing a dart at a map of the state is also a continuous variable. Elevation can take any value within the range between the lowest and highest points in California, making it a continuous variable.
03

Identify the type of variable for the distance a ruler snaps

The distance from the left edge at which a 12 -inch plastic ruler snaps when bent sufficiently to break is a continuous variable. The ruler can snap at any point along its length, making the distance a value within a continuous range.
04

Identify the type of variable for the price per gallon of gas

The price per gallon paid by the next customer to buy gas at a particular station is a discrete variable. This is because although it can vary, it'll only do so in countable increments, like cents. For example, the price can be $2.59, $2.60 or $2.61 per gallon, but it cannot be $2.595.

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Key Concepts

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

Numerical Variables
Numerical variables are values expressed in numbers rather than categories or labels. They help us measure, quantify, or express quantities. These variables can be dissected into two types: continuous and discrete.

Overall, numerical variables play a crucial role in statistical analysis because they can be easily measured and provide a wide range of insights. In various fields such as science, economics, and social studies, numerical data is often utilized for understanding trends, making predictions, and making informed decisions.
  • Continuous Variables: These can take any value within a range.
  • Discrete Variables: These can only take specific, separated values.
Keeping these definitions in mind, let's explore continuous and discrete variables in more detail.
Continuous Variables
Continuous variables are types of numerical variables that can take an infinite number of values within a specified range. This means they can be any number, including fractions and decimals, making them more precise.

For example, the length of a 1-year-old rattlesnake is a continuous variable. It can span from a minimal length like 10 inches to longer lengths yet be any fractional inch in between.

Measuring continuous variables is often done through tools like rulers, thermometers, or scales, allowing for high precision. In statistical analysis, this provides an opportunity to conduct more detailed models and analyses using continuous data.
  • Examples include measurements like weight, height, temperature, and time.
  • Tools such as graphs and calculus are usually used to analyze continuous data due to its nature of being infinitely variable.
Continuous variables enable detailed understanding and modeling thanks to their flexibility in value range.
Discrete Variables
Discrete variables differ from their continuous counterparts by only taking distinct, separate values. You can think of them as countable. They are typically represented by whole numbers, capturing clear and distinct units.

An example of a discrete variable is the price per gallon of gas at a station. A gas price might be $2.50, $2.51, or $2.60, but it won't fetch a mid-point price like $2.505. Since it's represented in definite amounts, it doesn't have fractional parts.
  • Typical examples include the number of students in a class, the result of rolling dice, or the count of books on a shelf.
  • Discrete variables often capitalize on methods like counting, tallying, and basic arithmetic for analysis.
Discrete variables are invaluable in scenarios where precise counts or totals are needed.
Statistical Analysis
Statistical analysis plays a pivotal role in evaluating both continuous and discrete variables. It involves using mathematical techniques to analyze, interpret, and make sense of numerical data.

By understanding the nature of each variable, statisticians can apply the proper methods to derive meaningful insights. Continuous data might lead to regression models or time-series analysis, while discrete data might suggest frequency distribution or simple descriptive statistics.
  • Allows identification of patterns, trends, and relationships in data.
  • Guidelines the decision-making process by providing a base of evidence.
  • Varies in methodology according to whether variables are continuous or discrete.
Statistical analysis serves as the foundation of research, emphasizing the significance of correctly identifying the type of numerical variable involved.

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Most popular questions from this chapter

For each of the following situations, give a set of possible data values that might arise from making the observations described. a. The manufacturer for each of the next 10 automobiles to pass through a given intersection is noted. b. The grade point average for each of the 15 seniors in a statistics class is determined. c. The number of gas pumps in use at each of 20 gas stations at a particular time is determined. d. The actual net weight of each of 12 bags of fertilizer having a labeled weight of 50 pounds is determined. e. Fifteen different radio stations are monitored during a 1 -hour period, and the amount of time devoted to commercials is determined for each.

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