A farmer buys a used tractor for ₹ 180000. He pays ₹ 90000 in cash and agrees to pays the balance in annual instalments of ₹ 9000 plus 12% interset on the unpaid amount. How much did the tractor cost him ?

A farmer buys a used tractor for ₹ 180000. He pays ₹ 90000 in cash

1.	A farmer buys a used tractor for ₹ 180000. He pays ₹ 90000 in cash and agrees to pays the balance in annual instalments of ₹ 9000 plus 12% interset on the unpaid amount. How much did the tractor cost him ?
Answer» Correct Answer - ₹ 239400 Total cost = ₹ 180000. paid in cash = ₹ 90000. Balance = ₹ 90000. Amount of each instalment = ₹ 9000. Number of instalments = ` 90000/9000 = 10` 1st instalment = `₹ ( 9000 + 90000 xx 12/100 xx1) = ₹ 19800` 2nd instalment = `₹ (9000 +81000 xx 12/100 xx 1) = ₹ 18720` 3rd instalment = `₹ ( 9000 + 72000 xx 12/100 xx 1) =₹ 17460` and so on. Total payment = ₹ [ 90000 + ( 19800 + 18720 +17640 + ..... up to 10 terms ] ` = ₹ [ 90000 +10/2 . { 39600 +9 xx (-1080) }]` = ₹ (90000 + 149400 ) = ₹ 239400.