Given,
Present value, P = Rs. 500000, Depreciated value, A = Rs 364500
The rate of depreciation, R =10% per annum.
Let the depreciation period be of n years.
We have, A=P[1−R100]n
Then, 364500=500000(1−10100)n
⇒36455000=(910)n
⇒7291000=(910)n⇒(910)3=(910)n⇒n=3
Hence, in 3 years the value of the flat be reduced to Rs 364500.