I've been searching everywhere on Khan Academy for this: What is a natural number, and is there a place on KA where I can find something about this?

The natural numbers are all whole numbers, excepting 0. 0 is a whole number but not a natural number because it does not have a positive or negative value.

why is -5 not a whole number its is a type of number ?

Whole numbers are numbers which are not FRACTIONS , DECIMALS or NEGATIVES. They are numbers from 1 to Infinity and 0. [0, 1, 2, 3 ...] While -5 is neither a FRACTION nor a DECIMAL , it is still a NEGATIVE for which it is not a WHOLE number. Negative Non-Fractional,Non-Decimal numbers are not whole numbers. Only Positive Non-Fractional,Non-Decimal numbers are whole numbers including Zero. Integers are the numbers which include both WHOLE numbers and their NEGATIVES (Non-Fractional,Non-Decimal Negatives). [... -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5 ...] So -5 obviously falls under that category. Therefore, -5 is an Integer , not a Whole number ! Hope it helps !

what type of number is .33%

It is rational. A percent that is equal to .0033 as a decimal and 33/10000 as a fraction.

Are all square rooted numbers irrational?

Not all square roots are irrational like the square of 9 is three or the square root of 16 is 4 but a lot of numbers are irrational. The square root of a number is if it multiplies by self to get that number. (Like 5*5=25 and the square root of 25 is 5). I hope that makes sense!!

what are non terminating numbers?

They are numbers like pi, √2, etc. When you express these numbers in decimals, they never stop. These are called irrational numbers. Also, infinity is also not terminating. (Technically, it's not a number. It's just a statement that the number is getting bigger.)

I dont really understand classyfing numbers .

Classifying numbers is the act of putting numbers into categories, which is why there are so many subsets or the Real Numbers, like the Integers or the Whole Numbers. Putting them into categories is actually quite easy. Natural Numbers are all positive numbers except 0 (1-infinity), Whole Numbers are Natural Numbers + 0 (0, 1-infinity), Integers are Whole Numbers + Negative Numbers (-1, 0, 1, etc...), and Rational Numbers are any number that can be expressed as a fraction. There are also Irrational Numbers, which are a variety of things, but all the subsets I just listed are the main subsets, but there are more than those. Hope this helps!

Why is a fraction rational?

Rational Numbers can be whole numbers, integers, and/or even decimals that can be expressed as a fraction. If a number does not qualify as a rational number, then it is irrational.

Would it be accurate to say that whole numbers are positive numbers and zero?

This is partially correct. The whole numbers are the positive *integers* and zero. (Note that for example, 1/2 is a positive number that is not a whole number.) Have a blessed, wonderful day!

If there are real numbers, would there be such a thing as fake numbers? Or are all numbers real?

No, not all numbers are *real* - some numbers are *imaginary* instead. (_There are no "fake" numbers..._) Hope this helps!

I thought there were natural numbers in rational. 1,2,3,4,5,ect.

There are... For some reason, Sal chose not to show them as an individual set on this page.

Main content

8th grade

Course: 8th grade > Unit 1

Lesson 3: Irrational numbers

Classifying numbers review

CCSS.Math:

8.NS.A.1

Google Classroom

Review whole numbers, integers, rational, and irrational numbers. Then, practice identifying each.

Whole numbers

start color #1fab54, start text, W, h, o, l, e, space, n, u, m, b, e, r, s, end text, end color #1fab54 are numbers that do not need to be represented with a fraction or decimal. Also, whole numbers cannot be negative. In other words, whole numbers are the counting numbers and zero.

Examples of whole numbers:

4, comma, 952, comma, 0, comma, 73

Integers

start color #11accd, start text, I, n, t, e, g, e, r, s, end text, end color #11accd are whole numbers and their opposites. Therefore, integers can be negative.

Examples of integers:

12, comma, 0, comma, minus, 9, comma, minus, 810

Rational numbers

start color #7854ab, start text, R, a, t, i, o, n, a, l, space, n, u, m, b, e, r, s, end text, end color #7854ab are numbers that can be expressed as a fraction of two integers.

Examples of rational numbers:

44, comma, 0, point, start overline, 12, end overline, comma, minus, start fraction, 18, divided by, 5, end fraction, comma, square root of, 36, end square root

Irrational numbers

start color #ca337c, start text, I, r, r, a, t, i, o, n, a, l, space, n, u, m, b, e, r, s, end text, end color #ca337c are numbers that cannot be expressed as a fraction of two integers.

Examples of irrational numbers:

minus, 4, pi, comma, square root of, 3, end square root

How are the types of number related?

The following diagram shows that all whole numbers are integers, and all integers are rational numbers. Numbers that are not rational are called irrational.

Want to learn more about classifying numbers? Check out this video.

Practice

Problem 1

Current

What type of number is square root of, 5, end square root?

Want to try more problems like this? Check out these exercises:
Classify numbers: rational & irrational
Classifying numbers

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Redapple8787
Posted 6 years ago. Direct link to Redapple8787's post “I've been searching every...”
I've been searching everywhere on Khan Academy for this: What is a natural number, and is there a place on KA where I can find something about this?
Button navigates to signup pageComment on Redapple8787's post “I've been searching every...”
(39 votes)
Answer
- Logan Herr
  Posted 5 years ago. Direct link to Logan Herr's post “The natural numbers are a...”
  The natural numbers are all whole numbers, excepting 0. 0 is a whole number but not a natural number because it does not have a positive or negative value.
  Comment on Logan Herr's post “The natural numbers are a...”
  (65 votes)
pedetin2015
Posted 5 years ago. Direct link to pedetin2015's post “why is -5 not a whole num...”
why is -5 not a whole number its is a type of number ?
Button navigates to signup pageComment on pedetin2015's post “why is -5 not a whole num...”
(12 votes)
Answer
- Sidharth Sunil
  Posted 5 years ago. Direct link to Sidharth Sunil's post “Whole numbers are numbers...”
  Whole numbers are numbers which are not FRACTIONS , DECIMALS or NEGATIVES.
  They are numbers from 1 to Infinity and 0. [0, 1, 2, 3 ...]
  
  While -5 is neither a FRACTION nor a DECIMAL , it is still a NEGATIVE for which it is not a WHOLE number.
  
  Negative Non-Fractional,Non-Decimal numbers are not whole numbers.
  Only Positive Non-Fractional,Non-Decimal numbers are whole numbers including Zero.
  
  Integers are the numbers which include both WHOLE numbers and their NEGATIVES (Non-Fractional,Non-Decimal Negatives). [... -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5 ...]
  So -5 obviously falls under that category.
  
  Therefore,
  -5 is an Integer , not a Whole number !
  
  Hope it helps !
  Comment on Sidharth Sunil's post “Whole numbers are numbers...”
  (37 votes)
Pierre Tétreau
Posted 4 years ago. Direct link to Pierre Tétreau's post “what type of number is .3...”
what type of number is .33%
Button navigates to signup pageComment on Pierre Tétreau's post “what type of number is .3...”
(10 votes)
Answer
- David Severin
  Posted 4 years ago. Direct link to David Severin's post “It is rational. A percen...”
  It is rational. A percent that is equal to .0033 as a decimal and 33/10000 as a fraction.
  Comment on David Severin's post “It is rational. A percen...”
  (26 votes)
Mehul prince
Posted 5 years ago. Direct link to Mehul prince's post “what are non terminating ...”
what are non terminating numbers?
Button navigates to signup pageComment on Mehul prince's post “what are non terminating ...”
(7 votes)
Answer
- David Lee
  Posted 5 years ago. Direct link to David Lee's post “They are numbers like pi,...”
  They are numbers like pi, √2, etc. When you express these numbers in decimals, they never stop. These are called irrational numbers. Also, infinity is also not terminating. (Technically, it's not a number. It's just a statement that the number is getting bigger.)
  Comment on David Lee's post “They are numbers like pi,...”
  (18 votes)
StephenPianoMan
Posted 3 years ago. Direct link to StephenPianoMan's post “Are all square rooted num...”
Are all square rooted numbers irrational?
Button navigates to signup pageComment on StephenPianoMan's post “Are all square rooted num...”
(8 votes)
Answer
- C Ethan Smith
  Posted 3 years ago. Direct link to C Ethan Smith's post “Not all square roots are ...”
  Not all square roots are irrational like the square of 9 is three or the square root of 16 is 4 but a lot of numbers are irrational. The square root of a number is if it multiplies by self to get that number. (Like 5*5=25 and the square root of 25 is 5). I hope that makes sense!!
  Comment on C Ethan Smith's post “Not all square roots are ...”
  (6 votes)
Edumacated
Posted 4 years ago. Direct link to Edumacated's post “Would it be accurate to s...”
Would it be accurate to say that whole numbers are positive numbers and zero?
Button navigates to signup pageComment on Edumacated's post “Would it be accurate to s...”
(4 votes)
Answer
- Ian Pulizzotto
  Posted 4 years ago. Direct link to Ian Pulizzotto's post “This is partially correct...”
  This is partially correct. The whole numbers are the positive integers and zero. (Note that for example, 1/2 is a positive number that is not a whole number.)
  
  Have a blessed, wonderful day!
  Button navigates to signup page
  (7 votes)
n.bur2993
Posted 2 years ago. Direct link to n.bur2993's post “I dont really understand ...”
I dont really understand classyfing numbers .
Button navigates to signup pageComment on n.bur2993's post “I dont really understand ...”
(5 votes)
Answer
- rylanhoyt
  Posted 7 months ago. Direct link to rylanhoyt's post “Classifying numbers is th...”
  Classifying numbers is the act of putting numbers into categories, which is why there are so many subsets or the Real Numbers, like the Integers or the Whole Numbers. Putting them into categories is actually quite easy. Natural Numbers are all positive numbers except 0 (1-infinity), Whole Numbers are Natural Numbers + 0 (0, 1-infinity), Integers are Whole Numbers + Negative Numbers (-1, 0, 1, etc...), and Rational Numbers are any number that can be expressed as a fraction. There are also Irrational Numbers, which are a variety of things, but all the subsets I just listed are the main subsets, but there are more than those.
  
  Hope this helps!
  Comment on rylanhoyt's post “Classifying numbers is th...”
  (3 votes)
Simeon
Posted 2 years ago. Direct link to Simeon's post “Why is a fraction rationa...”
Why is a fraction rational?
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(5 votes)
Answer
- ⭐BEST20042007⭐
  Posted 2 years ago. Direct link to ⭐BEST20042007⭐'s post “Rational Numbers can be w...”
  Rational Numbers can be whole numbers, integers, and/or even decimals that can be expressed as a fraction. If a number does not qualify as a rational number, then it is irrational.
  Comment on ⭐BEST20042007⭐'s post “Rational Numbers can be w...”
  (3 votes)
Xixiqiqi
Posted 4 years ago. Direct link to Xixiqiqi's post “If there are real numbers...”
If there are real numbers, would there be such a thing as fake numbers? Or are all numbers real?
Button navigates to signup pageComment on Xixiqiqi's post “If there are real numbers...”
(4 votes)
Answer
- Polina Vitić
  Posted 4 years ago. Direct link to Polina Vitić's post “No, not all numbers are *...”
  No, not all numbers are real - some numbers are imaginary instead.
  (There are no "fake" numbers...)
  
  Hope this helps!
  Comment on Polina Vitić's post “No, not all numbers are *...”
  (2 votes)
Avani Bharadwa
Posted 5 years ago. Direct link to Avani Bharadwa's post “I thought there were natu...”
I thought there were natural numbers in rational. 1,2,3,4,5,ect.
Button navigates to signup pageButton navigates to signup page
(1 vote)
Answer
- Kim Seidel
  Posted 5 years ago. Direct link to Kim Seidel's post “There are... For some rea...”
  There are... For some reason, Sal chose not to show them as an individual set on this page.
  Button navigates to signup page
  (6 votes)