Answer:
(This list is in the order that they are asked)
1:4
4:1
1:2
2:1
5:1
1:5
Explanation:
Start with Side length : Perimeter
6 : 24 = 1 : 4
Next, Perimeter : Side length
24 : 6 = 4 : 1
Radius : Diameter
4 : 8 = 1 : 2
Diameter : Radius
8 : 4 = 2 : 1
People : Tables
15 : 3 = 5 : 1
Tables to people
3 : 15 = 1 : 5