6/10 can be simplified but we don't need to worry about it right now. We only need to worry about simplifying 20/100:
20/100 → 10/50 → 5/25 → 1/5
Find common denominators
1/5 → 2/10
6/10
Now, add.
6/10 + 2/10 = 8/10
Therefore, the equation is true.
Best of Luck!