Find the sum on which the compound interest for 3 years at 10% per annum amounts to ₹ 1655.

At what rate per cent per annum will ₹ 6000 amount to ₹ 6615 in 2 years when interest is compounded annually ?

On a certain sum, the compound interest in 2 years amounts to ₹ 4240. If the rates of interest for successive years are 10% and 15% respectively, find the sum.

At what rate per cent compound interest, does a sum of money become 1.44 times of itself in 2 years ?