A sum of money doubles itself in 8 years. What is the rate of interest?

a. A sum of money doubles itself in 4 years at a certain rate of interest. In how many years will it triple itself at the same rate of interest ? b. A sum of money trebles itself in 6 years at a certain rate of interest. In how many years will it become four times itself at the same rate of interest ?

A sum of money doubles itself in 3 years. At same rate of simple interest, for a period of 9 years, how many times will the sum become?

If a sum of money doubles itself in 8 years at simple interest, the rate percent per annum is____

A certain sum of money doubles itself & number of years is equal to rate of interest. Find the rate of interest.

The interest on a certain sum of money is 0*24 times of itself in 3 years. Find the rate of interest.

A sum of money, lent out at simple interest, doubles itself in 8 years. Find : (i) the rate of interest. (ii) In how many years will the sum become triple (three times) of itself at the same rate percent ?

The rate per cent per annum at which the sum of money double itself in 16 yr at simple interest is

A sum of money invested at compound interest doubles itself in 6 years. At the same rate of interest it will amount to eight times of itself in: