A sum of money becomes 3 times in 12 years. In how many years it will become 5 times at the same rate of simple interest?

The simple interest on a sum of money for 3 years is ₹240 and the compound interest on the same sum, at the same rate  for 2 years is ₹170. The rate of interest is 

A certain sum doubles in 7 years at simple interest. The same sum under the same interest rate will become 4 times in how many years.:

2 years, a sum was put at SI at a certain rate. If the rate was 3 % higher, it would have fetched 300 more. What will be the sum? 

If the difference of interest of two banks of Rs 500 is Rs 2.50, find the difference between their rates.

In a certain time, the ratio of a certain principle and interest obtained from it are in the ratio 10 : 3 at 10 % interest per annum. The number of years for which the money was invested is? 

Rs. 2,000 is invested at 10% p.a. on simple interest. If that interest is added to the principal after every 20 years, the amount will become Rs. 14,000 after

₹ 500 was invested at 12 % per annum simple interest and another certain sum of money invested at 10 % per annum simple interest . If the total interest on both the sum after 4 years is 480, the latter sum of money is