A father left a will of Rs.35 mn 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 mn 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?

Explanation:

It is given that when both the daughters reach the age of 21, the amounts they get are equal.

The elder sister’s money earns interest only for a period of 5 years, while that of the younger sister earns interest for 12.5 years.

Therefore, if ‘x’ is the amount that the elder sister gets,

x+x×5×10\100=(35−x)×12.5×10\100+(35−x)

or 100x+50x=100(35−x)+125(35−x)

or 150x=225(35−x) or 150x=7875−225x

or 375x=7875 or x=21 mn