When dividing fractions, theres this thing you do call "keep, change, flip"
You keep the first fraction the same, change the division to a multiplication, and change the fraction to have the numbers flipped.
4 = 4/1
1 1/8 = 9/8
4/1 * 8/9 = 32/9
32/9 = 3 5/9
3 5/9 is the final answer