Question

Ravi invested Rs. 6000 in a scheme for 3 years which promised a certain percentage of simple interest on the sum. The interest offered was 5% for the first year, 7% for the second year and 9% for the third year. What was the amount that Ravi got after 3 years? ​

Answer 1

$Principal (P) = Rs \: 6000$

$Rate \: of \: Interest \: for \: first \: year (r_{1})=5\%$

$Rate \: of \: Interest \: for \: second \: year (r_{2})=7\%$

$Rate \: of \: Interest \: for \: Third \: year (r_{3})=9\%$

$Let \: Amount = A$

$\boxed{\pink{A = P\Big( 1 +\frac{r_{1}}{100}\Big)\Big( 1 +\frac{r_{2}}{100}\Big)\Big( 1 +\frac{r_{3}}{100}\Big)}}$

$A = 6000\Big( 1+\frac{5}{100}\Big)\Big( 1+\frac{57}{100}\Big)\Big( 1+\frac{9}{100}\Big)$

$= 6000\times \frac{105}{100} \times \frac{107}{100} \times \frac{109}{100}$

$= Rs \: 7347.69$

Therefore.,

$\red{ Amount \: that \:Ravi\: got \: after \: 3 \:yrs}$

$\green { = Rs \: 7347.69}$

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