Classify the following as rational number and irrational number: 5.7

Explanation:
Rational number:1. A rational number is a number that is expressed as $\frac{p}{q}$, where p and q are integers, and $q\ne 0$. Ex. $2,\frac{1}{4},\frac{11}{7},...$
2. Irrational number: An irrational number is a number that cannot be expressed as $\frac{p}{q}$, where p and q are integers, and $q\ne 0$.
Ex.$2,3,11,...$
We have number is 5.7.
This is one way to write this number:
$5.7=\frac{57}{10}$
Here, 57 and 10 are integers.
Hence, 5.7 can be written in the form of $\frac{p}{q}$, where p and q are integers, and $q\ne 0$.
Therefore, 5.7 is a rational number.