Calculate the amount and compound interest on

(a) Rs 10,800 for 3 years at per annum compounded annually.


(b) Rs 18,000 for years at 10% per annum compounded annually.


(c) Rs 62,500 for years at 8% per annum compounded half yearly.


(d) Rs 8,000 for 1 year at 9% per annum compounded half yearly.


(You could use the year by year calculation using SI formula to verify).


(e) Rs 10,000 for 1 year at 8% per annum compounded half yearly.

(a) Here, Principal (P) = Rs. 10800, Time (n) = 3 years,


Rate of interest (R) = 12 1/2 % = (25/2)%




= Rs. 15,377.34


Compound Interest (C.I.) = A – P


= Rs. 10800 – Rs. 15377.34 = Rs. 4,577.34


(b) Here, Principal (P) = Rs. 18,000, Time (n) = 2 1/2 years, Rate of interest (R) = 10% p.a.




= Rs. 21,780


Interest for 1/2 years on Rs. 21,780 at rate of 10% =


= Rs. 1,089


Total amount for 2 1/2 years


= Rs. 21,780 + Rs. 1089 = Rs. 22,869


Compound Interest (C.I.) = A – P


= Rs. 22869 – Rs. 18000 = Rs. 4,869


(c) Here, Principal (P) = Rs. 62500, Time (n) = 3/2 years = 3 years (compounded half yearly)


Rate of interest (R) = 8% = 4% (compounded half yearly)


Amount (A)



= Rs. 70,304


Compound Interest (C.I.) = A – P


= Rs. 70304 – Rs. 62500 = Rs. 7,804


(d) Here, Principal (P) = Rs. 8000, Time (n) = 1 years = 2 years(compounded half yearly)


Rate of interest (R) = 9% = (compounded half yearly)


Amount (A)



= Rs. 8,736.20


Compound Interest (C.I.) = A – P


= Rs. 8736.20 – Rs. 8000


= Rs. 736.20


(e) Here, Principal (P) = Rs. 10,000, Time (n) = 1 years = 2 years (compounded half yearly)


Rate of interest (R) = 8% = 4% (compounded half yearly)




= Rs. 10,816


Compound Interest (C.I.) = A – P


= Rs. 10,816 – Rs. 10,000 = Rs. 816


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