A certain sum is invested at a simple interest rate of 12% per annum for a certain period of time. If the sum becomes four times the principal at the end of the period, what is the duration of the investment?

What sum (in ₹) will earn a simple interest of ₹840 in 3 years at 20% per year rate of interest?

Simple interest of ₹375 is obtained on a sum of money for a period of 3 years at a rate of 2% per annum. Find the sum (in ₹).

A sum amounts to ₹ 9075 in $$1\frac{1}{3}$$​ years at 15% p.a, interest compounded 8-monthly. What is the simple interest (in ₹) on the same sum for the same period and at the same rate of interest ?

In how much time will a sum of money ₹7500 earn an interest of ₹150 at the rate of 4% per annum simple interest?

The simple interest on a certain sum for $$4\frac{2}{9}$$​ years at the rate of 4.5% per annum is ₹8,778. What will be the amount payable on the same sum at the rate of 5.5% per annum simple interest in $$2\frac{5}{7}$$​ years?

The simple interest on a principal amount is Rs. 714 for a period of 3 years at the rate of 7% per annum.

Amit invests a sum of Rs. 5400 and Gopal invests a sum of Rs. 10200 at the same rate of simple interest per annum. If, at the end of 4 years, Gopal gets Rs. 960 more interest than Amit, then find the rate of interest per annum (in percentage).

A certain sum invested at simple interest amounts to Rs. 8,411 in 3$$\frac 12$$​ years and to Rs. 9,776 in 6 years at thesame rate of interest per annum. What is the rate of interest per annum?

Gopal invests a sum of Rs. 5400 and Akshay invests a sum of Rs. 9400 at the same rate of simple interest per annum. If, at the end of 6 years, Akshay gets Rs. 720 more interest than Gopal, then find the rate of interest per annum (in percentage).

Akshay invests a sum of Rs. 5400 and Atul invests a sum of Rs. 9400 at the same rate of simple interest per annum. If, at the end of 6 years, Atul gets Rs. 360 more interest than Akshay, then find the rate of interest per annum (in percentage).