First, we want to reduce to lowest terms. To do that we need to find the GCF (greatest common factor)
The factors for 6 are: 1, 2, 3, 6
The factors for 8 are: 1, 2, 4, 8
GCF = 2
So, we divide each number by GCF 2
6 ÷ 2 = 3
8 ÷ 2 = 4
So, 6/8 = 3/4
Now to change the 3/4 into a decimal just divide
= 3 ÷ 4
= 0.75
6/8 = .75
Hope this helps. :)