Question

Lataben borrowed some money from a bank at a rate
of 10 pic.p.a interest for 25 years to start cottage
industry. If she paid 1025 rupees as total interest
how much money had she borrowed?

​

Answer 1

$\large\textsf{ }$

$\LARGE\textsf{\underline\textcolor{aqua}{↭ GiVeN :-}}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{Rate of interest ( R ) = 10 p.c.p.a.}$

$\qquad\tt{:}\longrightarrow\large\textsf{Time Period ( T ) = 25 years }$

$\qquad\tt{:}\longrightarrow\large\textsf{Amount paid as an interest ( S.I. ) = Rs. 1025}$

$\large\textsf{ }$

$\LARGE\textsf{\underline\textcolor{aqua}{↭ To FiNd :-}}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{Amount borrowed from the bank ( P ) = ?}$

$\large\textsf{ }$

$\LARGE\textsf{\underline\textcolor{aqua}{↭ FoRmUla :-}}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\boxed{\large\textsf\textcolor{purple}{ S.I. = \cfrac{\large\textsf{P × T × R}}{\large\textsf{100}} }}$

$\large\textsf{ }$

$\LARGE\textsf{\underline\textcolor{aqua}{↭ SoLuTioN :-}}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{ S.I. = \cfrac{\large\textsf{P × T × R}}{\large\textsf{100}} }$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{ 1025 = \cfrac{\large\sf{P} × \cancel{25} × 10}{\cancel{\large\textsf{100}}} }$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{ 1025 = \cfrac{\large\textsf{P × 10}}{\large\textsf{4}} ------ ( 25 × 4 = 100)}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{ \cfrac{\large\textsf{1205 × 4}}{\large\textsf{10}} = P}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\large\textsf{ \cfrac{\large\textsf{4100}}{\large\textsf{10}} = P}$

$\large\textsf{ }$

$\qquad\tt{:}\longrightarrow\boxed{\large\textsf\textcolor{red}{410 = P}}$

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$\large\textsf\textcolor{orange}{∴ The amount borrowed = Rs. 410}$