When considering yes, or for that matter no, voters the numbers do not accurately reflect the position.
As I understand it a 33%, for instance, worker has a whole vote as does a 100% worker.
On the day the actual number of potential strikers is probably a lot less than the voting figures would indicate.
A strike would have to last quite a while to get through all those part timers.
You may even find that some of the non striking part timers would be prepared to move into being 100% workers to cover strikers and earn a bit of extra money.
It is a pity we don't have the numbers of "full time equivalent" voters.