# Is sqrt400 a rational or irrational number?

##### 1 Answer
Jul 9, 2015

sqrt(400 = 20, so it is a rational number.

#### Explanation:

Before answering the question, we must simplify if possible.

$\sqrt{400} = \sqrt{4 \cdot 100} = \sqrt{4} \cdot \sqrt{100} = 2 \cdot 10 = 20$