Question

please answer the questions please and explain it also! if you want brainlist so answer questions please!
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Answer 1

Answer:

1.

i. Rs 307.5

ii. Rs 630.5

iv. Rs 208

Step-by-step explanation:

${\underline{{\text{Using Formula}}}}$

${{\boxed{ C.I = P \{ (1+ \frac{r}{100})^ {t} -1 \} }}}$

Where,

C.I = Compound Interest

P = Principal

t = time

r = rate of interest

${\underline{{\text{Solution:}}}}$

i. Amount

$3000(1 + \frac{5}{100}) {}^{2} \\ \\ = 3000( \frac{105}{100} ) {}^{2} \\ \\ = 3000 {( \frac{21}{20} )}^{2} \\ \\ = 3000 \times \frac{21}{20} \times \frac{21}{20} \\ \\ = \cancel{3000} \times \frac{21}{ \cancel{20}} \times \frac{21}{ \cancel{20}} \\ \\ = 15 \times \frac{441}{2} \\ \\ = \frac{6615}{2} \\ \\ = 3307.5$

C.I = Rs ( 3305.8 - 3000) = Rs 307.5

ii. Amount

$4000(1 + \frac{5}{100}) {}^{3} \\ \\ = 4000( \frac{105}{100} ) {}^{3} \\ \\ = 4000 {( \frac{21}{20} )}^{3} \\ \\ = 4000\times \frac{21}{20} \times \frac{21}{20} \times \frac{21}{20} \\ \\ = \cancel{4000} \times \frac{21}{ \cancel{20}} \times \frac{21}{ \cancel{20}} \times \frac{21}{ \cancel{20}}\\ \\ = \frac{9261}{2} \\ \\ = 4630.5$

C.I = Rs (4630.5 - 4000) = Rs 630.5

iv.

$1250(1 + \frac{8}{100}) {}^{2} \\ \\ = 1250( \frac{108}{100} ) {}^{2} \\ \\ = 1250 {( \frac{27}{25} )}^{2} \\ \\ = 1250\times \frac{27}{25} \times \frac{27}{25} \\ \\ = \cancel{1250} \times \frac{27}{ \cancel{25}} \times \frac{27}{ \cancel{25}} \\ \\ = 2 \times 729 \\ \\ = 1458$

C.I = Rs (1458 - 1250) = Rs 208

Answer 2

Answer:

1) 306.5

2)632

3)207.5