Compound Interest Questions and Answers

$text{Amount} = text{ Rs. } 800 times bigg(1 + frac{5}{100} bigg)^2 times bigg(1 + frac{5}{200}bigg)$
= Rs. 904.05

$text{Sum} = frac{A}{ big(1 +frac{r}{100} big)^n } = frac{2809}{ big(1 + frac{6}{100} big)^2}$

$text{Sum} = frac{A} { bigg(1 +frac{r}{100} bigg)^n } = frac{2809}{bigg(1 + frac{6}{100} bigg)^2}$

$$

$=frac{2809 times 2500}{53 times 53} = text{Rs.} 2500$

Interest in one year

= Rs. 2977.54 - Rs. 2809 =  Rs. 168.54

Principal = Rs. 2809, Int. = Rs. 168.54

Time = 1 year

$therefore text {Rate } = frac{16854 times 100}{100 times 2809} = 6$

Interest for 1 year on Rs. 20 is 80 P.

$text{Rate}$

$text{88200} = 80000 Big(1 + frac{x}{100}Big)^2$

$therefore Big(1 + frac{x}{100} Big)^2 = frac{441}{400} = Big( frac{21}{20}Big)^2$

$x = 5$

$x times Big(1 + frac{20}{100}Big)^n > 2x$

$text {or} Big(frac{6}{5}Big)^n > 2, text{ it is true if } n = 4$

$text{Principal } = frac{1352}{left( 1 + frac{4}{100}right)^2 }$

$= 1352 times frac{625}{676} = text{Rs. } 1250$

$4x = xBig(1 + frac {r}{100} Big)^2$

$therefore Big(1 + frac{r}{100} Big)^2 = 40 text{ or } 1 + frac{r}{100} = 2$

$text{or } r =100$

$text{Amount} = 800 times Big(1 + frac{5}{100}Big)^3$

$= 800 times frac{9261}{8000} = 926.10$

$therefore text{ Interest} = text{Rs.} 926.10 - text{Rs.} 800 = text{Rs.} 126.10$

$text{ Capital } = frac{10000}{Big( 1 + frac{25}{100} Big)^3 } = text{Rs. } 5120$