Explanation: Here, P = Rs 2668, T = 5 yr, a =Rs 4669
As we know
Amount (a) = principle (p) + SI (simple interest)
4669 = 2668 + SI
SI = 4668 - 2668 = Rs 2001
Again, we know, SI = P x R x T / 100
2001= 2668 x r x 5/100
R = 2001 x 100 / 2668 x 5 = 2001 x 5/667 = 15%

Explanation: Here, p = Rs 25800, R = 14%
T = 1 yr 4month
= (1 + 4/ 12) = (1 + 1/3) = 4 / 3 yr
Now SI = P x R x T /100 = 25800 x 14 x 4/3 /100
= 258 x 14 x 4 / 3 = Rs 4816