Question

The rate of simple intrest per annum reduces from 4%to15/4% and for this,a person's annual incom decreases by Rs 60. Determine the principle of that person?​

Answer 1

$\huge\star\underline\mathfrak\green{Answer}$

Let the principle amount be Rs. x

Simple interest at 4% in 1 year (let) =

$\frac{p \times r \times t}{100}$

=

$\frac{x \times 4 \times 1}{100}$

=

$\frac{x}{25}$

Amount = S. I. + Principle

=

$\frac{x}{25} + x$

=

$\frac{26x}{25}$

Now,

Simple interest at 15/4% in t years :

$\frac{x \times 4 \times 1}{5 \times 100}$

=

$\frac{x}{125}$

Amount =

$\frac{x}{125} + x$

=

$\frac{126x}{125}$

according to question,

amount at 4% - Rs. 60= amount at 5/4%

=

$\frac{26x}{25} - 60 = \frac{126x}{125}$

Principle= Rs. 1875

Answer 2

$\huge\star\underline\mathbb\red{HELLO}$

The principle is Rs. 1875