求分数乘法简便计算题多给点好吗?

24×5/6 2/9 + 1/3 3/19 ×57 1/2 + 1/3 4/5 × 5/8 2 - 13/8
1/4 + 5/6 3/4 - 3/5 1- 2/3 - 1/3 2/5 + 3/5 - 2//5 + 35 1/10 × 9 + 1/10
7/10 ×10/1- 7/10 8/9 ×8/9 ÷8/9 ×8/9 3/5 × 9/9 + 3/5
( 4/7 + 8/9 )×2/25 15/21 ×3/4 + 10/21 ×3/4 - 3/4 3/45 ×2/5
3/6×34/35 ( 5/6 - 5/9 )×18/5