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By using the formula, find the amount and compound interest on:Rs 9000 for 2 years 4 months at 10 % per annum compounded annually.
Solution
Given: Principal (P)=Rs. 9000
Rate (R)=10% per annum
Time (n)=2 years 4 months
=213 years [∵1 year =12 months]
Amount for 2 years
∴ Amount (A)=P(1+R100)n
=Rs. 9000 (1+10100)2
=Rs. 9000×1110×1110
=Rs. 10890
For the next 13 years, Principal = Amount for 2 years =Rs. 10890.
Interest for 13 years =P×R×n100
=(10890×10×13100)
=Rs. 363
So, the total Amount for 213 years =Rs. 10890+363=Rs. 11253
∴C.I.=A−P=Rs. 11253−Rs.9000
=Rs. 2253
Mathematics
Secondary School Mathematics VIII
Standard VIII