• # question_answer The value of a machine depreciates every year by 10%. If the present value of the machine is Rs.100000, what will be its value after three years? A)  20250                         B)  72900C)  90000             D)  81000

(b): The value of the machine after depreciation of 10% per year for 3 years = $Rs.\,100000\times \frac{90}{100}\times \frac{90}{100}\times \frac{90}{100}=72900/-$ Tip: $9\times 9\times 9$may be remembered as 729 It may also be remembered as, ${{3}^{2}}\times {{3}^{2}}\times {{3}^{2}}={{3}^{6}}$which is 729 (by doing so you are also are also revising your concepts learnt in previous chapter).