Question

Find the simple interest on Rs $4000$ at $7.5\%$ p.a. for $3$ years $3$ months. Also, find the amount.

Answer 1

Given,

Principal , $P=$ Rs $4000$

Rate of interest, $r=7.5\%$ p.a. $=\frac{15}{2}\%$ p.a.

Time , $t=3years3months$

$=3\frac{3}{12}$years

$=3\frac{1}{4}$years $=\frac{13}{4}$ years

Hence,

Simple Interest , $I=\frac{P\times r\times t}{100}$

$=\frac{4000\times \frac{15}{2}\times \frac{13}{4}}{100}$

$=\frac{4000\times 15\times 13}{100\times 2\times 4}$

On simplification, we get,

$I=5\times 15\times 13=$ Rs $975$

Therefore,

Amount $=P+I$

$=14000+975=14975$

Hence, simple interest is Rs $975$ and the amount is Rs $14975$.