I think that 2/4 would be bigger because 2/4 is the same as 1/2 and 1/2 is bigger than 1/8. Imagine a pizza, if i have 1/2 of a whole pizza i would have more pizza than a friend who had 1/8 of the whole pizza.
If you simplify 2/4, you will get 1/2. 1/2 is bigger than 1/8.
Proof:
Draw 2 mental circles in your head. then draw lines that will make the circles out of 2 and out of 8. Now color in 1/2 of the first circle and 1/8 of the second circle. You can see that the 1/2 is bigger than the 1/8.
