Answer :

3/4 is greater than 8/12. Multiply 3 & 4 by 3 to get a common denominator.
First, both denominators must be the same to easily understand this. So, the common denominator for 4 and 12 are 12. Whatever you do for the bottom you must do for the top as well. So, 3(3)=9/4(3)=12. 8(1)=8/12(1)=12. Therefore your new fractions are: 9/12 (AKA 3/4), and 8/12. 9/12 less than 8/12 (visually)