What Real number is
Real numbers are the set of all numbers that can be represented on a number line. They include both rational and irrational numbers, and they are used in mathematics to represent continuous quantities.
Real numbers can be broken down into several categories, including natural numbers, integers, rational numbers, irrational numbers, and complex numbers.
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Natural Numbers: Natural numbers are the set of all positive whole numbers, including 0. They are represented by the symbol N.
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Integers: Integers are the set of all numbers that can be written without a fractional component. They include both positive and negative whole numbers, and they are represented by the symbol Z.
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Rational Numbers: Rational numbers are the set of all numbers that can be written as a fraction. They include both positive and negative numbers, and they are represented by the symbol Q.
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Irrational Numbers: Irrational numbers are the set of all numbers that cannot be written as a fraction. They include both positive and negative numbers, and they are represented by the symbol R.
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Complex Numbers: Complex numbers are the set of all numbers that can be written as a sum of a real and an imaginary part. They are represented by the symbol C.
Examples
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Real numbers are used to represent continuous values in statistics. For example, the height of a person or the temperature of a room can be represented by real numbers.
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Real numbers are used to measure the average of a group of data. For example, the average salary of a group of employees can be calculated using real numbers.
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Real numbers are used to calculate the probability of an event occurring. For example, the probability of a coin landing heads can be calculated using real numbers.
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Real numbers are used to measure the variability of a group of data. For example, the standard deviation of a group of exam scores can be calculated using real numbers.