From the problem, we have a fraction of 6/8
To rewrite this in simpliest form, we need to divide the numerator and the denominator by a common factor.
For 6, we have :
6 = 2 x 3
For 8, we have :
8 = 2 x 2 x 2
As you can see, the common factor between 6 and 8 is 2.
So we need to divide the numerator and denominator by 2.
This will be :

The answer is 3/4