Question

Rs 2000 amounts to Rs 2226.05 in two years at compound interest .The rate of interest is?

Answer 1

Solution :

Given principal ( p ) = Rs2000

Amount ( A ) = Rs2226.05

Time ( T ) = 2years

Number of times Interest paid (n)= 2

Now ,

A = p( 1 + r/100 )ⁿ

=> 2226.05 = 2000( 1 + r/100 )²

=> 222605/( 100× 2000 ) =( 1 + r/100 )²

=> ( 5×44521)/(5×20×2000)=( 1 + r/100)²

=> 444521/40000 = ( 1 + r/100 )²

=> ( 211/200 )² = ( 1 + r/100 )²

=> 211/200 = 1 + r/100

=> 211/200 - 1 = r/100

=> ( 211 - 200 )/200 = r/100

=> ( 11 × 100 )/200 = r

=> 11/2 = r

=> r = 5.5 %

Or

r = 5½ %


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