• # question_answer The installation cost of a machine is Rs. 2000. The cost of repairs increases Rs.  40 annual). The scrap value of the machine is Rs. 200. The economic repair life of the machine is nearly: A) $5\frac{1}{2}$ Years                B) $7\frac{1}{2}$ years           C) $9\frac{1}{2}$ Years                D) $11\frac{1}{2}$ years

Economic repair life, $x={{\left[ \frac{2(C-S)}{b} \right]}^{1/2}}$ $x={{\left[ \frac{2(200-200)}{400} \right]}^{1/2}}=9.5\,years$