Four-person fire teams and the ACV's thirteen passengers

How many Marines are in the fire team and rifle squad used in the ACV capacity comparison?

Four in a fire team, and thirteen in the described squad: a squad leader and three fire teams.

The organization used in the ACV comparison has four people in a Marine fire team, correcting the initial guess of seven. A team leader, automatic rifleman, grenadier, and rifleman divide its functions. Three such teams plus a squad leader produce the thirteen-person rifle squad described here. That explains why thirteen passenger places are meaningful in the vehicle-capacity comparison. A heavier weapons element is also discussed as a possible substitute for one team during an amphibious operation.