A Motorbike can be purchased on cash payment of Rs.

Solution

Cash Price = Rs. 30000 Less Cash Down Payment = Rs. 7000 Balance = Rs. (30000 - 7000) = Rs. 23000 First Installment = Rs. 8000 Balance = Rs. (23000 - 8000) = Rs. 15000 Second Installment = Rs. 8000 Balance = Rs.(15000 - 8000) = Rs. 7000 Third Installment = Rs. 8000 Balance = Rs. 1000 Now Interest on First year = (23000 × r × 1)/100 Interest on Second year = (15000 × r × 1)/100 Interest of Third year = (7000 × r ×1)/100 Now, according to the question, (23000 × r ×1 )/100 + (15000 × r ×1)/100 + (7000 × r ×1 )/100 = 1000 [1000r × (23+15+7)]/100 = 1000 45r/100 = 1 r = 100/45 = 20/9%