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The whole numbers are the natural numbers together with 0. (Note: a few textbooks disagree and say the natural numbers include 0 .) The sum of any two natural numbers is also a natural number (for example, 4 + 2000 = 2004 ), and the product of any two natural numbers is a natural number ( 4 × 2000 = 8000 ).

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Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.

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The sum of any two natural numbers is always a natural number. This is called ‘Closure property of addition’ of natural numbers. Thus, N is closed under addition. If a and b are any two natural numbers, then (a + b) is also a natural number. Example : 2 + 4 = 6 is a natural number. (ii) Commutative property : Addition of two natural numbers ...

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Rational Numbers. Can be expressed as the quotient of two integers (ie a fraction) with a denominator that is not zero.Many people are surprised to know that a repeating decimal is a rational number. The venn diagram below shows examples of all the different types of rational, irrational nubmers including integers, whole numbers, repeating decimals and more.

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Every natural number can be expressed as a product of prime numbers. If the number is already prime, its decomposition is itself multiplied by one. If not, it is divided into the smallest prime number by which it is divisible (it can be one or several times), until a prime number is obtained. For example: 5 = 5 * 1. 15 = 3 * 5. 28 = 2 * 2 * 7.

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Squares. The square of a number is the number multiplied by itself. For e.g. square of 4 = 4 2 = (4 × 4) = 16; Perfect squares are squares of whole numbers.; Some examples of perfect squares are 1 2 = 1, 2 2 = 4, 3 2 = 9, 4 2 = 16, 5 2 = 25, 6 2 = 36; Square roots

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A simple way to think about the Real Numbers is: any point anywhere on the number line (not just the whole numbers). Examples: 1.5, -12.3, 99, √2, π. They are called "Real" numbers because they are not Imaginary Numbers. Read More -> Imaginary Numbers. Numbers that when squared give a negative result.

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1, 2, 3 or 0, 1, 2, 3 - it depends if you consider 0 as a natural number or not - there are two methods for the set of the natural numbers - one with “0” and the ...

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Now we will discuss about the examples of finite sets and infinite sets. Examples of finite set: 1. Let P = {5, 10, 15, 20, 25, 30} Then, P is a finite set and n(P) = 6. 2. Let Q = {natural numbers less than 25} Then, Q is a finite set and n(P) = 24. 3. Let R = {whole numbers between 5 and 45} Then, R is a finite set and n(R) = 38. 4.

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Ordinal numbers are in direct contrast with cardinal numbers (also called natural numbers and integers), which represent countable quantities. Learning Ordinals If you are teaching ordinals to English language learners or young students, introduce the concept by reviewing cardinal numbers, then continue with ordinals and compare and contrast ...