which is greater 5/8 or 2/4?

5/8

Here’s the general rule for comparing fractions.  It will help when you have a timed test.

If a/b and c/d are equal, bc = ad  (The product of the means equals the product
of the extremes.) 

If a/b > c/d, then bc < cd  (The
product of the means is less than the product of the extremes.

You can probably guess the relationship between bc and cd if a/b
< c/d.

Try it with these two fractions: A/b = 1/2 and c/d = 3/8