Question

2. If a certain sum of money amounts to Rs. 16,940 in 6 years at 9%, with
simple interest then find the principal amount? ​

Answer 1

Step-by-step explanation:

Hi,

Amount = 16940

Time = 6 years

Rate of interest = 9%

Let principal be X.

S.I = Principal × Rate × Time / 100

S.I = X × 9 × 6 /100

S.I = 27X/50

Now,

Amount = Principal + S.I

16940 = x + 27x/50

16940 = (50x + 27x)/50

77x = 16940 × 50

77x = 847000

X = 847000/77

X = 11000

Hence,

Principal = X = 11000..

Hope it will help you :))

Answer 2

AnswEr :

$\bf{\green{\underline{\underline{\bf{Given\::}}}}}$

If a certain sum of money amounts to Rs.16940 in 6 years at 9% with simple interest.

$\bf{\red{\underline{\underline{\bf{To\:find\::}}}}}$

The principal.

$\bf{\orange{\underline{\underline{\bf{Explanation\::}}}}}$

Let the principal be Rs. R

$\star$We know that formula of the Simple Interest (S.I.) :

$\bf{\large{\boxed{\bf{Simple\:Interest\:(S.I.)=\frac{P*R*T}{100} }}}}}}}}}$

A/q

$\longmapsto\tt{S.I.=\dfrac{R*9*6}{100} }\\\\\\\\\longmapsto\tt{S.I.=\cancel{\dfrac{54R}{100}} }\\\\\\\\\longmapsto\tt{\red{S.I.=\dfrac{27R}{50}-----(1)}}$

We know that;

Principal = Amount - Interest.

oR

$\leadsto\tt{Amount=Principal+Interest}\\\\\\\leadsto\tt{16940=R+\dfrac{27R}{50} }\\\\\\\leadsto\tt{16940=\dfrac{50R+27R}{50} }\\\\\\\leadsto\tt{16940\times 50=50R+27R}\\\\\\\leadsto\tt{16940\times 50=77R}\\\\\\\leadsto\tt{R=\dfrac{\cancel{16940}\times 50}{\cancel{77}} }\\\\\\\leadsto\tt{R=Rs.(220\times 50)}\\\\\\\leadsto\tt{\red{R=Rs.11000}}$

∴ The principal amount is Rs.11000 .