Question

the difference between the compound interest compound annually and simple interest on a certain sum for 2 years at 4 per annum is rupees 20 find the sum

Answer 1

P(1+4/100)^2 - (P×2×4/100)
=P(26/25)^2-(2P/25)
=676P/625 - 50P/625
= 626P/625

Now , accordingly,
626P/625 = 20
P = 19.9680
P= 19.97