Compound Interest

Compound Interest :                   

                                                          
If P is Principal amount, R is Percentage Rate, n is number of years

Rule : When interest is compound annually :

 

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Rule : If interest is compounded Half-yearly :

 

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Rule : When interest is compounded Quarterly :

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Rule : When rate of interest are X % , Y %, Z % for 1st, 2nd and third year respectively. Then amount will be :

 

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Rule : When interest is compounded annually but time is in fraction such as

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Ex. A sum of money doubles itself at compound interest in 15 years. In how many years will it become eight times ?
Solution :

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Ex. The difference between compound interest and simple interest on an amount of Rs. 15, 000 for 2 years is Rs. 96. What is the rate of interest per annum ?

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Ex. A sum of money is lent out at compound interest rate of 20 % per annum for two years. It would fetch Rs. 482 more if interest is compounded half-yearly. Find the sum