Suppose you borrow $200 from a payday lender for one week at a weekly rate of 10%. You'll obviously owe $220 at the end of a week. If you are unable to repay the loan, however, the lender will say that you now owe not only $220 but also 10% of that $220 at the end of the second week. How much will you owe by the end of the second week?