Question

60. Amar borrowed 800 at a rate of
interest of 5% per annum. The
amount he will pay after 3 years is:
(1) 3920
3940
(3) 960 (4) 980​

Answer 1

Answer:

920

Step-by-step explanation:

principal=800

Time=3years

Rate of Interest=5%

first find the interest

Interest=p*r/100*t

Interest=800*5/100*3

Interest=8*5*3

Interest=120

Amount= Interest+principal

Amount=120+800

Amount=920

Answer 2

AnswEr :

$\frak{ Given}\begin{cases}\texttt{Principal = Rs. 800}\\\texttt{Rate = 5\% p.a.}\\\texttt{Time = 3 years}\end{cases}$

$\rule{150}{1}$

$\underline{\bigstar\:\textsf{Amount at Simple Interest Annually :}}$

$\longrightarrow\tt Amount=Principal+Simple\: Interest\\\\\\\longrightarrow\tt Amount=P+\dfrac{(P \times r \times t)}{100}\\\\\\\longrightarrow\tt Amount=800 + \dfrac{(800 \times 5 \times 3)}{100}\\\\\\\longrightarrow\tt Amount=800 + (8 \times 5 \times 3)\\\\\\\longrightarrow\tt Amount=800 + 120\\\\\\\longrightarrow\underline{\boxed{\red{\tt Amount=Rs. \:920}}}$

⠀

$\therefore\:\underline{\textsf{Amount will be \textbf{Rs. 920} at Simple Interest.}}$

$\rule{200}{2}$

$\underline{\bigstar\:\textsf{Amount when Compounded Annually :}}$

$\longrightarrow\tt Amount = P \times \bigg(1 +\dfrac{r}{100}\bigg)^{t}\\\\\\\longrightarrow\tt Amount = 800 \times \bigg(1 +\dfrac{5}{100}\bigg)^{3}\\\\\\\longrightarrow\tt Amount = 800 \times \bigg(1 +\dfrac{1}{20}\bigg)^{3}\\\\\\\longrightarrow\tt Amount = 800 \times \bigg(\dfrac{20 + 1}{20}\bigg)^{3}\\\\\\\longrightarrow\tt Amount = 800 \times \bigg(\dfrac{21}{20}\bigg)^{3}\\\\\\\longrightarrow\tt Amount =800 \times \dfrac{9261}{8000}\\\\\\\longrightarrow\tt Amount = \dfrac{9261}{10}\\\\\\\longrightarrow\underline{\boxed{\red{\tt Amount =Rs. \:926.10}}}$

⠀

$\therefore\:\underline{\textsf{Amount will be \textbf{Rs. 926.10} at Compound Interest.}}$