https://foxoyo.com/mcq/60371/nitin-borrowed-some-money-at-the-rate-of-6-per-annum-for-the-first-three-years-9-per-annum-for-the-next-five-years-and-13-per-annum-for-the-period-beyond-eight-years-if-the-total-interest-paid-by-him-at-the-end-of-eleven-years-is-rs-8160-how-much-money-did-he-borrow