What can you say about the sum of a rational number and an irrational number?
Question:

What can you say about the sum of a rational number and an irrational number?

Solution:

Sum of a rational number and an irrational number is an irrational number.

Example: $4+\sqrt{5}$ represents sum of rational and an irrational number where 4 is rational and $\sqrt{5}$ is irrational.