No it isn't. I already explained how. All the bank has to do is issue the loans, and those loans create the deposits.
Why can they only lend $90? Doing so would put their reserve ratio at above 50%. They can lend until it is at 10%.
Banks do not have to pay you interest for having money in a debit or checking account. If they do decide to do so, the amount is so minuscule that it is completely irrelevant to this discussion.
It is impossible for a bank with a single deposit of $100 to loan $900.
No it isn't. I already explained how. All the bank has to do is issue the loans, and those loans create the deposits.
Yes, a bank with a single deposit of $100 (plus extra deposits of $900) can loan out $900.
Of course those extra deposits change my claim of a single deposit of $100.
A deposit of $100 (and $999,900 more) allows loans of $900,000. So what?
Why can they only lend $90? Doing so would put their reserve ratio at above 50%.
Nope, lending out $90 leaves reserves at $10. Because $100-$90 = $10.
Banks do not have to pay you interest for having money in a debit or checking account.
In the stupid example, the bank was charging 10% interest. It's safe to say the people depositing the proceeds of earlier loans will want to be paid interest.
After the loans were made, they need $1800 in new deposits or $1800 borrowed from other banks or the Fed.
Without that extra step, the $200 allows only $180 in loans.