Okay, so first you do 3/5 + 2/3. The least common denominatior of 5 and 3 is 15.
5x3=15 so, 3x3 = 9 So, 3/5 = 9/15
3x5=15 so, 2x5 = 10 So, 2/3 = 10/15
10/15 + 9/15 = 19/15.
19/15 = 1 4/15
Hope I helped. Sorry I'm giving you an answer pretty late, but I just saw this.