No, banks can't lend more than they borrow (and most of the money they borrow is deposits from customers and loans from other banks, not the central bank). They

No, banks can't lend more than they borrow (and most of the money they borrow is deposits from customers and loans from other banks, not the central bank). They can lend part of the money they take in deposits, but they must hold a fraction of it in reserve – hence fractional-reserve banking. The minimum reserve is set in law.