In how much time will a sum of Rs. 12500 amounts to Rs. 20000 at the rate of 8 percent per annum at simple interest?

The simple interest on a sum for 5 years is one fourth of the sum. The rate of interest per annum is

A sum of money at simple interest amounts to ₹ 1,012 in $$2{1\over2}\%$$ years and to ₹ 1,067.20 in 4 years. The rate of interest per annum is:

 If 64 amount to 83.20 in 2 years what will ₹ 86 amount to in 4 years at the same rate percent per annum? 

A sum of money becomes Rs 16000 in 6 years at the rate of 25% per annum simple interest. What is the total interest for 6 years?

At what rate per cent per annum will a sum of money double in 8 years?

What would be the simple interest obtained on an amount of `6,535 at the rate of 10 % p.a. (percent per annum) after 6 years?

A sum of money amounts to 5,200 in 5 years and to 5,680 in 7 years at simple interest. The rate of interest per annum is-