The interest earned on Rs 15000 in 3 years at simple interest is Rs 5400. Find the rate of interest per annum?

12%

Simple interest for 3 years - 5400

Simple interest for 1 year - 1800

Formulae for SI = \(\frac{\text{P Χ R Χ T} }{ 100}\) 

Putting the values in the formulae:

1800 = \(\frac{\text{15000 Χ R Χ 1} }{ 100}\) 

1800 = \(\frac{\text{15000R} }{ 100}\) 

1800 = 150R

R = \(\frac{1800 }{150 }\)

R = 12%