At what rate percent will ₹2000 amount to ₹2315.25 in 3 years at compound interest?

If ₹40000 amounts to ₹48620.25 in 2 years, compound interest payable half-yearly, find the rate of interest per annum.

At what rate percent p.a. compound interest would ₹80000 amount to ₹88200 in two years, interest being compounded yearly. Also find the amount after 3 years at the above rate of compound interest.

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.