Hey there! :D
Any repeating number is rational.
The square root of 108 is 10. 3923048454
It is irrational. Its numbers do not repeat.
So, if you were to multiply a rational and irrational number, it would be irrational.
We can even test this:
.17171717171717171717171*10.392304....= 1.784537....
I hope this helps!
~kaiker