Step-by-step explanation:

1. 5/6 × 2/3

= (5×2) / (6×3)

= 10/18

= 5/9

= 0.55555555556

2.7/1 × 2/3

= (7×2) / (1×3)

= 14/3 or 4 2/3

= 4.6666666667

3.4/20 × 2/5

= (4×2) / (20×5)

= 8/100

= 2/25

= 0.08

4.10 5/6 × 3 1/3

= 65/6 × 10/3

= (65×10) / (6×3)

= 650/18

= 325/9 or 36 1/9

= 36.111111111

5.9/20 × 25/27

= (9×25) / (20×27)

= 225/540

= 5/12

= 0.41666666667

6. 20/1 / 2/3

= (20×3) / (1×2)

= 60/2

= 30/1

= 30

7.5/12 / 3/4

= (5×4) / (12×3)

= 20/36

= 5/9

= 0.55555555556

8.5/50 / 20/35

= (5×35) / (50×20)

= 175/1000

= 7/40

= 0.175

9.5 3/4 / 6 2/3

= 23/4 / 20/3

= (23×3) / (4×20)

= 69/80

= 0.8625

10.9/6 / 3/4

= (9×4) / (6×3)

= 36/18

= 2/1

= 2