# In which set(s) of numbers would you find the number sqrt80 - irrational number - whole number - rational number - integer - real number - natural number

Question
Irrational numbers
In which set(s) of numbers would you find the number $$\displaystyle\sqrt{{80}}$$
- irrational number
- whole number
- rational number
- integer
- real number
- natural number

2021-02-09
Natural numbers is the set of counting numbers i.e. 1, 2, 3,…
So $$\displaystyle\sqrt{{80}}$$ is not present in this set.
Whole numbers is the set of natural numbers along with 0 i.e. 0, 1, 2,…
So $$\displaystyle\sqrt{{80}}$$ is not present in this set.
Integers are set of whole numbers along with negative numbers i.e. …,-2, -1, 0, 1, 2,…
So $$\displaystyle\sqrt{{80}}$$ is not present in this set.
Rational numbers are set of numbers that can be expressed in the form $$\displaystyle\frac{{p}}{{q}}.$$
So $$\displaystyle\sqrt{{80}}$$ is not present in this set.
Irrational numbers are set of numbers that cannot be expressed in the form $$\displaystyle\frac{{p}}{{q}}.$$
Hence $$\displaystyle\sqrt{{80}}$$ is present in this set.
Real numbers are set of rational and irrational numbers together.
Hence $$\displaystyle\sqrt{{80}}$$ is present in this set.
Answer: Irrational number and Real number.

### Relevant Questions

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b) whole numbers
c) integers
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e) irrational numbers
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True or False?
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