3/5 + 3/20

To add these fractions, we need to have a common denominator. The lowest common denominator for 5 and 20 is 20. So, we can rewrite the fractions as follows:

3/5 = 12/20
3/20 = 3/20

Now, we can add the fractions:

12/20 + 3/20 = (12 + 3) / 20 = 15/20

Therefore, 3/5 + 3/20 = 15/20.