2/3 × 7/5 - 4/15 = 14/15 - 4/15 = 10/15 = 2/3
3/4 ÷ 4/5 + 7/2 = 3/4 × 5/4 + 7/2 = 15/16 + 56/16 = 71/16
1/2 + 5/2 + 7/10 = 5/10 + 25/10 + 7/10 = 37/10
4/7 + 15/7 ÷ 5/2 = 4/7 + 15/7 × 2/5 = 4/7 + 30/35 = 20/35 + 30/35 = 50/35 = 10/7
1 - 5/2 × 4/15 = 1 - 20/30 = 30/30 - 20/30 = 10/30 = 1/3
2/7 + 5/14 × (2/3 + 1/3) = 2/7 + 5/14 × 1 = 4/14 + 5/14 = 9/14