In mathematics, a rational number is any number that can be expressed as a ratio of two integers numbers, being a non-zero denominator.
Answers
-5 is rational because can be writen as -5/1
√11 is irrational because can't be written as a ratio.
2/3 is rational because is a ratio of two integer numbers.
0.5 is rational because can be written 1/2
√16 is rational because can be written 4/1
pi (π) is irrational because can't be written as a ratio