4/7 + 3/4 3cale 2/7 - 1cala 5/7 5/12 + 9 20 3/5 / 4/7

4/7 + 3/4= 16/28 + 21/28=37/28=1 i 9/28 5/12 + 9/20 = 50/120 + 55/120=105/120=21/24 3/5 / 4/7 = 3/5 × 7/4 = 21/20 = 1.05