Question

Find simple interest of 180 at 3 % for
1¼ years.​

Answer 1

Answer :-

Simple interest = ₹6.75

Given :-

• Principal = ₹180
• Time = 1¼ years = 5/4 years
• Rate = 3% per annum

To find :-

Simple interest calculated on the amount

Formula to use :-

$simple \: interest = \dfrac{principal \times time \times rate}{100}$

Substituting the values,

$si = \dfrac{180 \times 3 \times \frac{5}{4} }{100}$

$si = \dfrac{540 \times \frac{5}{4} }{100}$

Reducing to the lowest terms in the numerator,

$si = \dfrac{ \cancel{540} \times \frac{5}{ \cancel{4}} }{100}$

$si = \dfrac{135 \times 5}{100}$

$\dfrac{675}{100}$

$si = ₹6.75$

Hence the simple interest = ₹6.75

Some more formulas :-

$time = \dfrac{simple \: interest \times 100}{principal \times rate}$

$principal = \dfrac{simple \: interest \times 100}{rate \times time}$

$rate = \dfrac{simple \: interest \times 100}{principal \times time}$

$Amount = Principal + Interest$

Answer 2

given that ,

p=180₹,T=1 1/4 =5/4,R = 3%

I=PRT/100 = 180×3×5/4

________________

100

=675/100

=6.75%