This is the classic description found in the economic textbooks. Unfortunately it is incorrect, the system doesn't work that way. (See comments above).

apropos btw. I've never actually seen a banking system that has a 10% ratio, I think that was Keynes chosing easy numbers. The reserve ratio back in his day was more like 20-25%, these days it is down to about 1-2% in most countries, and being replaced with terms like "required liquidity ratios".