Compound Interest — Prelims Questions

A sum of money invested at compound interest amounts to ₹4,840 in 2 years and ₹5,324 in 3 years. What is the rate of interest per annum?

The compound interest on a certain sum for 2 years at 10% per annum is ₹420. What would be the simple interest on the same sum for the same period at the same rate?

A population of bacteria doubles every 3 hours. If the initial population is 1000, what will be the population after 12 hours?

If ₹10,000 is invested at 20% per annum compounded half-yearly, what will be the amount after 1.5 years?

The difference between compound interest and simple interest on a sum for 3 years at 10% per annum is ₹93. Find the principal amount.