The value of a flat worth ₹ 500000 is depreciating at the rate of 10\% p.a. In how many years will its value be reduced to ₹ 364500?
(a)3 years
(b)4 years
(c)5 years
(d)6 years
Answer
Answer (as printed): A
Explanation
Let the required time be $n$ years. Then, $500000\left(1-\frac{10}{100}\right)^{n}=364500$ $$\begin{aligned} & \Rightarrow \quad\left(\frac{9}{10}\right)^{n}=\frac{364500}{500000}=\frac{729}{1000} \\ & \Rightarrow \quad\left(\frac{9}{10}\right)^{n}=\left(\frac{9}{10}\right)^{3} \Rightarrow n=3 . \end{aligned}$$
Explanation as extracted from the printed page; notation may be imperfect.