Rooney, Hernandez, and Robin race each other in a 100 meters race. All of them run at a constant speed throughout the race.
Rooney beats Hernandez by 20 meters.
Hernandez beats Robin by 20 meters.
How many meters does Rooney beat Robin by ?	Choose the correct option.
A) 33 meters.  B) 29 meters.  C) 25 meters.  D) 36 meters.  E) 30 meters.
D   36 meters.   100/v1 = 80/v2   100/v2 = 80/v3   20+(20/v2)*v3=20+16= 
<gadget id="calculator">20+16</gadget>
<output>36</output>
36
<result>D</result>
Rooney, Hernandez, and Robin race each other in a 100 meters race. All of them run at a constant speed throughout the race.
Rooney beats Hernandez by 20 meters.
Hernandez beats Robin by 20 meters.
How many meters does Rooney beat Robin by ?