If $R=7\frac{1}{2}\%p.a.$ $T=2\frac{1}{2}years$ ,$I=Rs.\text{7}.\text{5}0$ then the principal is _____.

$T=2\frac{1}{2}=\frac{5}{2}years$

$I=$ Rs.$\text{7}.\text{5}0$ ; $p=?$

We know that $I=\frac{PTR}{100}$

$P=\frac{100\times I}{TR}$ $=\frac{100\times 7.50}{\frac{15}{2}\times \frac{5}{2}}$

$=\frac{750\times 4}{75}=$ Rs. 40