The difference between the compound interest and the simple interest on a certain sum at 5% per annum for 2 years is Rs. 1.50. The sum is?

Let the sum be Rs. 100 then,
S.I.= Rs.(100 x 5 x 2)/100 =Rs.10
C.l.= Rs.[100 x (1 +5/100)²] =Rs.41/4
∴ difference between C.I. and S.I. = Rs. (41/4-10) = Re.0.25
⇒ 0.25 : 1.50 : : 100 : P
∴ P = (1.50 x 100) / 0.25 = Rs. 600