So what you do is subtract 2 and 5/8 from 2/3.
1. make the denominators the same by using GCD
8 | 3
8*1=8 | 3*1=3
8*2=16 |3*2=6
8*3=24 |3*3=9
8*4=32 |3*4=12
8*5=40 |3*5=15
8*6=48 |3*6=18
8*7=56 |3*7=21
8*8=64 |3*8=24
8*9=72 |3*9=27
8*10=80 |3*10=30
2. find which ones they have in common, and use GCD to solve for the denominator
8 and 3 both have 24
so the GCD is 24
3. put your new problem in there
2 and 5/24 - 2/24= x
4.solve your problem for x
2 and 5/24 - 2/24= 2 and 3/24
5. now simplify 2 and 3/24
2 and 3/24 divided by 3= 2 and 1/8
6. so you can say
x = 2 and 1/8