'Twenty' in the Bible

Or what king, going out to confront another king in battle, will not sit down first and determine whether he is able with ten thousand to oppose the one coming against him with twenty thousand?

Now there were six stone water jars there for Jewish ceremonial washing, each holding twenty or thirty gallons.

In those days Peter stood up among the believers (a gathering of about one hundred and twenty people) and said,

They took soundings and found the water was twenty fathoms deep; when they had sailed a little farther they took soundings again and found it was fifteen fathoms deep.