An amount at the rate of 5% pa becomes ₹ 10 more at

An amount at the rate of 5% pa becomes ₹ 10 more at compound interest than that of simple interest after 2 yr. Calculate the principal.

Here, CI - SI = 10, R = 5%, n = 2 yr and P = ?
According to the formula,
CI - SI = PR²/100²
⇒ 10 = (P x 25)/10000
∴ P = (400 x 10) = ₹ 4000