(a) Principal (P) = Rs \(1200\)
Rate (R) = \(12 \%\) p.a.
Time (T) = \(3\) years
\(S.I = \frac{P\times R\times T}{100}\)
= \(\frac{1200\times 12\times3}{100}\)
= Rs \(432\)
Amount = \(P + S.I\).
= \(1200 + 432\)
= Rs \(1632\)
(b) P = Rs \(7500\), R = \(5\%\) p.a.
T = \(3\) years
\(S.I = \frac{P\times R\times T}{100}\)
\(=\frac{7500\times5\times3}{100}\)
= Rs \(1125\)
Amount = \(7500 + 1125\)
= Rs \(8625\)
Read more: Simple Interest Formula