A father left a will of Rs.35 lakhs between his two daughters aged 8.5 and 16 such that they may get equal amounts when each of them reach the age of 21 years. The original amount of Rs.35 lakhs has been instructed to be invested at 10% p.a. simple interest. How much did the elder daughter get at the time of the will?

Let Rs.x be the amount that the elder daughter got at the time of the will. Therefore, the younger daughter got (3,500,000 - x).

The elder daughter?s money earns interest for (21 - 16) = 5 years @ 10% p.a simple interest.

The younger daughter?s money earns interest for (21 - 8.5) = 12.5 years @ 10% p.a simple interest.

As the sum of money that each of the daughters get when they are 21 is the same,

  x + 5 * 10 * x 100 = 3 , 500 , 000 - x + 12 . 5 * 10 * 3 , 500 , 000 - x 100

  x + 50 x = 3 , 500 , 000 - x + 125 100 * 3 , 500 , 000 - 125 x 100

  2 x + 50 x 100 + 125 x 100 = 3 , 500 , 000 * 1 + 5 4

  200 x + 50 x + 125 x 100 = 9 4 * 3 , 500 , 000

 => x = 2 , 100 , 000 = 21 l a k h s