Just because you can fit 7 troops in an M2A2 bradley, doesn't mean anybody does it. In fact, most drive around with only 4-5.
However, a 2.5 ton truck has a max "official" capacity of like 14, but I've seen nearly 30 in them when its the only ride home.
Those are *capacities*, and there is no reason anything would ever be 100% capacity. In fact, 100% is really overloaded in most situations. I'd simply round down to the nearest unit. 4 platoon carriers would typically have 3 platoons, 12 would have 9, etc.
However, when it comes to vehicles things usually carry the maximum capacity.
Infantry just kinda find space where they can. I'm sure in the BTU the grunts on trips would make hammocks around the vehicles that transport them, engine compartments, hallways, whatever. Regardless tho, it'll smell like butt pretty quickly :)
- 12 years of Infantry experience