Under the Rural Housing Scheme, the Delhi Development Authority (DDA) allotted a house to Kamal Raj for Rs. 126100. This payment is to be made in three equal annual instalments. If the money is reckoned at 5% per annum compound interest, then how much is to be paid by Kamal Raj in each instalment ?

Explanation:-

Let the value of each instalment be Rs. x
Then, (P.W. of Rs. x due 1 year hence) + (P.W. of Rs. x due 2 year hence) + (P.W. of Rs. x due 3 year hence) = 126100 $$\eqalign{ & \Rightarrow \frac{x}{{\left( {1 + \frac{5}{{100}}} \right)}} + \frac{x}{{{{\left( {1 + \frac{5}{{100}}} \right)}^2}}} + \frac{x}{{{{\left( {1 + \frac{5}{{100}}} \right)}^3}}} = 126100 \cr & \Rightarrow \frac{{20x}}{{21}} + \frac{{41x}}{{441}} + \frac{{8000x}}{{9261}} = 126100 \cr & \Rightarrow \frac{{8820x + 8400x + 8000x}}{{9261}} = 126100 \cr & \Rightarrow \frac{{25220x}}{{9261}} = 126100 \cr & \Rightarrow x = \left( {\frac{{126100 \times 9261}}{{25220}}} \right) \cr & \Rightarrow x = 46305 \cr}$$