A person borrows some money for 5 years and ratio of loan amount : total interest amount is 5 : 2. Then find the ratio of loan amount : interest rate is equal to = ?

$$\eqalign{ & {\text{Loan Amount}}:{\text{Total Interest}} \cr & {\text{5}}:{\text{2}} \cr & {\text{Principal}} \to {\text{5}} \cr & {\text{Interest for 1 year}} \Rightarrow {\text{2}} \cr & {\text{Interest for 5 year}} \Rightarrow {\text{10}} \cr & {\text{10}} = \frac{{5 \times {\text{R}} \times 5}}{{100}} \cr & {\text{R}}\% = 40\% \cr & = \frac{{40}}{{100}} = \frac{2}{5} \cr & {\text{P}}:{\text{R}} = 5:\frac{2}{5} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\, = 25:2 \cr} $$