A sum of ₹ 400 amounts to ₹ 441 in 2 yr. What will be its amount, if the rate of interest is increased by 5%?

According to the given condition.
441 = 400 (1 + R/100)²
⇒ 441/400 = (1 + R/100)²
⇒ (21/20)² = (1 + R/100)²
⇒ 21/20 = 1 + R/100
⇒ (21/20) - 1 = R/100
⇒ R/100 = 1/20
∴ R = 5%
∴ new rate = 5 + 5 = 10%
∴ Amount = 400 (1 + 10/100)²
= 400 x (11/10) x (11/10)
= ₹ 484