9 3/20 + 7 4/15 = 16 + 3/20 + 4/15 = 16 + 3×3/20×3 + 4×4/15×4 = 16 + 9/60 + 16/60 = 16 + 9+16/20 = 16 25/60 = 16 5×5/12×5 = 16 5/12.
38 21/26 + 14 34/39 = 52 + 21/26 + 34/39 = 52 21×3/26×3 + 34×2/39×2 = 52 + 63/78 + 68/78 = 52 + 63+68/78 = 52 131/78 = 52 52+1×78/78 = 53 53/78.