If simple interest on sum of money for 3 years at 8% per annum is ₹ 7,500, find the compound interest on the same sum for the same period at same rate.

Calculate the amount and compound interest on ₹ 16,000 for 1 year at 15% per annum, compounded half yearly.

The simple interest on a sum of money at 12% per annum for 1 year is ₹ 900. Find :

(i) the sum of money and

(ii) the compound interest on this sum for 1 year, payable half-yearly at the same rate.