At what rate of compound interest per annum will a sum of ₹1,200 becomes ₹1,348.32 in 2 years?

If the compound interest on a sum for 2 years at 12½% per annum is ₹340, then the simple interest on the same sum at the same rate for the same period of time is

Find the least number of complete years in which a sum of money put out at the rate of 20% per annum compound interest will be more than double.

In what duration of time will ₹3300 become ₹3399 at 12% per annum interest compounded quarterly?

A sum of money doubles itself in 15 years at compound interest. In how many years it will become 8 times at the same compound interest rate?

There is 60% increase in an amount in 6 years at simple interest. What will be the compound interest (in ₹) on ₹12,000 after 3 years at the same rate of interest?