A. Rs. 1550 B. Rs. 1650 C. Rs. 1750 D. Rs. 2000 E. None of these Solution(By Examveda Team)$$\eqalign{ & {\text{C}}{\text{.I}}{\text{.}}\, = Rs.\,\left[ {4000 \times {{\left( {1 + \frac{{10}}{{100}}} \right)}^2} - 4000} \right] \cr & \,\,\,\,\,\,\,\,\,\,\,\,\, = Rs.\,\left( {4000 \times \frac{{11}}{{10}} \times \frac{{11}}{{10}} - 4000} \right) \cr & \,\,\,\,\,\,\,\,\,\,\,\,\, = Rs.\,840 \cr & \therefore {\text{Sum}} = Rs.\,\left( {\frac{{420 \times 100}}{{3 \times 8}}} \right) \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = Rs.\,1750 \cr} $$ Solution S.I=P×r×t100A=P(1+r100)tC.I=A−P Where, C. I = Compound interest S.I = Simple interest A = Amount P = Principal r = rate % t = time in years Given, compound interest on a certain sum of money at 5% per annum for 2 years is Rs. 246. ∴ r = 5% t = 2 years C.I = Rs. 246 P = ? A = C.I + P ⇒ A = P + 246 therefore, P+246=P(1+5100)2⇒P+246=P×1.052⇒246=1.1025P–P⇒246=0.1025P⇒P=2400 Now, S.I on the same sum for 3 years at 6% per annum. ∴ r = 6% t = 3 years S.I=(2400×6×3)100⇒S.I=Rs.432 The simple interest on the same sum for 3 years at 6% per annum is Rs. 432 |