There is no definite amount
People like to cheer for the football teams in the stadium full of many fans and people that are watching.
Many, many thousands of people joined the Union army.
one million people joined
a soccer cheer is a love of the game not just to win. soccer is a game the many people say the it is just fun.
20-7= 13... 13 people joined the softball team
Cheerleading got its name because you do a cheer and people cheer for you when you dance and there is always a leader for a cheer squad.
I think that its was about over 1000 people that have joined
It would be difficult to say exactly but there were thousands of people, including soldiers and ordinary people, who joined Hitler in his killing.