A certain sum amounts to ₹5292 in 2 years and to ₹5556.60 in 3 years at compound interest. Find the rate and the sum.

A certain sum amounts to ₹798.60 after 3 years and ₹878.46 after 4 years. Find the interest rate and the sum.

In what time will ₹1500 yield ₹496.50 as compound interest at 10% per annum compounded annually?

Find the time (in years) in which ₹12500 will produce ₹3246.40 as compound interest at 8% per annum, interest compounded annually.