'Fifties' in the Bible

Moreover thou shalt provide out of all the people able men, such as fear God, men of truth, hating unjust gain; and place such over them, to be rulers of thousands, rulers of hundreds, rulers of fifties, and rulers of tens:

And Moses chose able men out of all Israel, and made them heads over the people, rulers of thousands, rulers of hundreds, rulers of fifties, and rulers of tens.

So I took the heads of your tribes, wise men, and known, and made them heads over you, captains of thousands, and captains of hundreds, and captains of fifties, and captains of tens, and officers, according to your tribes.

and he will appoint them unto him for captains of thousands, and captains of fifties; and he will set some to plow his ground, and to reap his harvest, and to make his instruments of war, and the instruments of his chariots.

Behold, there came fire down from heaven, and consumed the two former captains of fifty with their fifties; but now let my life be precious in thy sight.