Find the principal if the interest compounded at the rate of 10% per annum for two years is Rs. 420.
A. Rs. 1000
B. Rs. 2200
C. Rs. 2000
D. Rs. 1100
E. Rs. 1200
Answer: Option C
Solution(By Examveda Team)
$$\eqalign{ & {\text{Given}}, \cr & {\text{Compound}}\,{\text{rate}},\,R = 10\% \,{\text{per}}\,{\text{annum}} \cr & {\text{Time}} = 2\,{\text{years}} \cr & CI - Rs.\,420 \cr & {\text{Let}}\,P\,{\text{be}}\,{\text{the}}\,{\text{required}}\,{\text{principal}} \cr & A = \left( {P + CI} \right) \cr & {\text{Amount}},A = \left\{ {P \times {{\left[ {1 + \left( {\frac{R}{{100}}} \right)} \right]}^n}} \right\} \cr & \left( {P + CI} \right) = \left\{ {P \times {{\left[ {1 + \frac{{10}}{{100}}} \right]}^2}} \right\} \cr & \left( {P + 420} \right) = P \times {\left[ {\frac{{11}}{{10}}} \right]^2} \cr & P - 1.21P = - 420 \cr & 0.21P = 420 \cr & {\text{Hence}},P = \frac{{420}}{{0.21}} = Rs.\,2000 \cr} $$Join The Discussion
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Related Questions on Interest
Find the simple interest on Rs. 5200 for 2 years at 6% per annum.
A. Rs. 450
B. Rs. 524
C. Rs. 600
D. Rs. 624
Rs. 1200 is lent out at 5% per annum simple interest for 3 years. Find the amount after 3 years.
A. Rs. 1380
B. Rs. 1290
C. Rs. 1470
D. Rs.1200
E. Rs. 1240
Interest obtained on a sum of Rs. 5000 for 3 years is Rs. 1500. Find the rate percent.
A. 8%
B. 9%
C. 10%
D. 11%
E. 12%
Rs. 2100 is lent at compound interest of 5% per annum for 2 years. Find the amount after two years.
A. Rs. 2300
B. Rs. 2315.25
C. Rs. 2310
D. Rs. 2320
E. None of these
How this 1.21 is come if we divide 11/10 we obtain 1.1