A sum of money at double the rate of simple interest doubles itself in 10 years. In how much time will that amount be triple of itself?

The simple interest on a sum  of money is $$8\over 25$$ of the sum. If the number of years is numerically half the rate percent per annum, then the rate percent per annum is 

In what time will the simple interest be $$ {2\over5} $$ of the principal at 8% per annum? 

A property fetches a net annual income of ₹1000 deducting all outgoings. The capitalized value of the property for the rate of interest 6% will be (in ₹) -

A sum of money becomes two times of itself in 8 years at simple interest, and it becomes four times of itself in 2 years at compound interest, when interest is compounded annually. Find the ratio of the rate of simple interest to the rate of compound interest offered per year.

What annual instalment will discharge a debt of ₹ 6450 due in 4 years at 5% simple interest?

A sum of money was invested at a certain rate of simple interest for 2 years. Had it been invested at 1% higher rate, it would have fetched Rs.192 more interest. The sum of money is-

The sum of money that will yield Rs. 60 as simple interest at the rate of 6% per annum in 5 years is-