Question

1428. Mr. Deepak invested an amount of Rs. 21250 for 6 yr. At what rate of SI will be obtain the total amount of Rs. 26350 at the end of 6 yr.?​

Answer 1

➤ Given :-

Principle :- ₹21250

Total amount :- ₹26350

Time :- 6 years

➤ To Find :-

Rate of interest of the given sum

➤ Formula required :-

${\tt \large \dashrightarrow \orange{\boxed{\tt \gray{\dfrac{SI \times 100}{P \times T}}}}}$

How to do :-

Here, we are given that Deepak invested ₹21250 and at end of 6 years he received ₹26350. We should find the rate of interest being paid. First, we should find the value of the simple interest by subtracting the total amount and the principle and then we should find the rate of interest by using the given formula.

➤ Solution :-

Simple Interest :-

${\tt \longrightarrow 26350 - 21250}$

${\tt \longrightarrow Rs \: \: 5100}$

Rate of interest :-

${\tt \longrightarrow \dfrac{5100 \times 100}{21250 \times 6}}$

${\tt \longrightarrow \dfrac{5100 \times \cancel{100}}{\cancel{21250} \times 6} = \dfrac{5100 \times 4}{850 \times 6}}$

${\tt \longrightarrow \dfrac{ \cancel{5100} \times 4}{850 \times \cancel{6}} = \dfrac{850 \times 4}{850 \times 1}}$

${\tt \longrightarrow \dfrac{\cancel{850} \times 4}{\cancel{850} \times 1} = \dfrac{1 \times 4}{1 \times 1}}$

${\tt \longrightarrow \cancel \dfrac{4}{1} = \boxed{\tt 4 \bf\%}}$

$\Huge\therefore$ The rate of interest being paid to Deepak is 4%.

━━━━━━━━━━━━━━━━━━━━━━

$\dashrightarrow$ Some related formulas :-

Simple Interest :- ${\boxed{\tt\dfrac{P \times R \times T}{100}}}$

Principle :- ${\boxed{\tt\dfrac{SI \times 100}{R \times T}}}$

Time :- ${\boxed{\tt\dfrac{SI \times 100}{P \times R}}}$