Compound Interest Dues Clearance

Year 1 start: Rs 4000. End of Year 1 amount $= 4000 \times 1.15 = 4600$. Repays Rs 1500 $\implies$ Balance $= 4600 - 1500 = 3100$. End of Year 2 amount $= 3100 \times 1.15 = 3565$. Repays Rs 1500 $\implies$ Balance $= 3565 - 1500 = 2065$. End of Year 3 amount $= 2065 \times 1.15 = 2374.75$. Repays Rs 1500, so additional amount needed $= 2374.75 - 1500 = \text{Rs. } 874.75$.