movement in combat, break down Options

[gamemaster]

hey guys ,got a question for ya,movement in combat has always ben a point of arguement in my group ,we understand how to determine how much one can move and all the penaltys associated with it ie...running mods ,walking mods ect....

our concern is when theres multiple initiative passes by multiple characters .how much can one move in each of there turns?

#1 26 initiative movement 18 [6X3]
#2 8 initiative movement 6 [2x3]
#3 15 initiative movement 12 [4x3]


just as an example use these stats and please explain how the rules would state how they move.the arguement in our group is this we seem to think that you divide the # of initiative passes you have by your movement and thats how many you can move in that initiative pass ,but it seems to make the faster characters actually move slower per each initiative pass because thay have to split of there movement across more initiative passes.this doesnt make sence to us someone help please.