# Quantitative Aptitude - Compound Interest - Formula & Concept Tutorial

Principal – P , Rate – R % per annum, Time = n year

- When Interest is compounded annually

Amount =

- When Interest is compounded half yearly

Amount =

- When Interest is compounded Quaterly

Amount =

- When Interest is compounded annually, but time is in fraction, say years

Amount =

- When Rates are different for different year, say R1%, R2%, R3% for 1
^{st}, 2^{nd}and 3^{rd}year respectively

Then, Amount =

- Present worth of Rs x , due n year hence is given by

Present Worth =

- Compound Interest ( CI ) = Amount – Principle
- When rate of interest is compounded ‘a’ times a year

Amount =