Let us write, by calculating the number of yrs. for which the interest of ₹600 at the rate of simple interest of 8% per annum will be ₹168.

An agricultural Co-operative society gives agricultural loan to its members at the rate of simple interest of 4% per annum. But an interest is to be given at the rate of simple interest of 7.4% per annum for a loan taken from the bank. If a farmer being a member of the Co-operative society takes a loan of ₹5000 from it instead of taking loan from the bank, the let us write, by calculating the money to be saved as interest per annum.

If the interest of ₹292 in 1 day be 1 paise, then let us write by calculating, the rate of simple interest in percent per annum.

If I get ₹1200 return as amount (principal along with interest) by depositing ₹800in the bankat the rate of simple interest of 10% per annum, then let us write by calculating, the time for which the money was deposited in the bank.

At the same rate of simple interest in percent per annum, if a principal becomes the amount of ₹7100 in 7 yrs. and of ₹6200 in 4 yrs., let us determine the principal and rate of simple interest in percent per annum.