Question

Rs 8000 became Rs 9261 in a certain interval of time at the rate of 5% per annum, C.I.. Find the time.

Answer 1

Answer:

$Time = 3 \: years\\C.I = Rs\:1261$

Step-by-step explanation:

$Given \\principal(P)=Rs\:8000,\\Amount(A)=Rs\:9261,\\Rate\:of\: interest (R)=5\% \:p.a,\\Let\:the \: number \:of\:times\\ \: interest \:paid =n$

$we\: know \:that \\</p><p>A=P\big(1+\frac{R}{100}\big)^{n}$

$\implies 9261=8000\big(1+\frac{5}{100}\big)^{n}$

$\implies \frac{9261}{8000}=\big(1+\frac{1}{20}\big)^{n}$

$\implies \frac{9261}{8000}=\big(\frac{20+1}{20}\big)^{n}$

$\implies\big( \frac{21}{20}\big)^{3}=\big(\frac{21}{20}\big)^{n}$

$\implies 3=n$

$Since,\: If \:a^{m}=a^{n} \implies\: m=n$

$C.I = A-P\\=Rs\:9261-Rs\:8000\\=Rs\:1261$

Therefore,.

$Time = 3 \: years\\C.I = Rs\:1261$

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Answer 2

Answer:3 years

Step-by-step explanation:

Is given below in the image