Find the compound interest on Rs 15625 for 9 months,

Given:

$\mathrm{P}=\mathrm{Rs} 15,625$

$\mathrm{R}=16 \%=\frac{16}{4}=4 \%$ quarterly

$\mathrm{n}=9$ months $=3$ quarters

We know that:

$\mathrm{A}=\mathrm{P}\left(1+\frac{\mathrm{R}}{100}\right)^{\mathrm{n}}$

$=$ Rs $15,625\left(1+\frac{4}{100}\right)^{3}$

$=$ Rs $15,625(1.04)^{3}$

$=$ Rs 17,576

Also,

$\mathrm{CI}=\mathrm{A}-\mathrm{P}$

$=$ Rs $17,576-$ Rs 15,625

$=$ Rs 1,951

Thus, the required compound interest is Rs 1,951 .