"For instance salary is 25% ish of the budget. One american soldier costs as much as 10 or 20 chinese ones so for the same amount of money they get 20x the manpower." t #102
The U.S. is reportedly paying about $1 $Million per troop per year in Afghanistan.
It's vastly less expensive to billet our troops Stateside.
I don't know how the " costs as much as 10 or 20 chinese ones " approximation was arrived at. But we should bear in mind, China's military occupation may be limited mainly to Tibet, and perhaps the islands it's dredging up in the South China Sea.
The other consideration is, our perhaps more high-tech equipment is a force-multiplier.
So even if China has a ~15:1 troop ratio advantage over U.S., that doesn't mean they'd have the advantage on the battle field.
Finally: what battlefield? I wouldn't lose a lot of sleep about Chinese troops marching into Peoria.
It's China's navy that seems to be the more immediate concern. And the U.S. Navy seems fairly well appointed.