Question

31. If I lend a sum of money at 6 per cent, the insterest for a certain time exceeds the loan by Rs 100 ; but if I lend it at 3 per cent, for a fourth of the time, the loan exceeds its interest by Rs 425 . How much do I lend?

Answer 1

Let the amount of loan be Rs.x and its interest exceeds the loan amount by Rs.100 in y years at 6% rate.

So x+100= xy6/100 ........(1)

By 2nd condition

x - xy3/400=425

Or, 8x - xy6/100=3400........(2)

Combining (1) and (2) we get

8x -x-100=3400

=>7x=3500

=>x = 500