Correct Answer - Option 1 : Rs. 484

**Given:**

Sum = Rs.400

Amount = Rs.441

Time = 2 years

**Formula Used:**

For compound interest,

A = P(1 + R/100)^{n}

where,

A = Amount

P = Sum

R = Rate of interest

n = Number of years

**Calculation:**

A = P(1 + R/100)n

⇒ 441 = 400(1 + R/100)^{2}

⇒ 441/400 = (1 + R/100)2

⇒ √(441/400) = 1 + R/100

⇒ 21/20 = (100 + R)/100

⇒ 21 = (100 + R)/5

⇒ 105 = 100 + R

⇒ R = 105 – 100

⇒ R = 5%

Now the rate of interest increased by 5%

⇒ Total rate of interest = 5% + 5%

⇒ Total rate of interest = 10%

A = P(1 + R/100)n

⇒ A = 400 (1 + 10/100)^{2}

⇒ A = 400 (1 + 1/10)^{2}

⇒ A = 400 (11/10)^{2}

⇒ A = 400 × 11/10 × 11/10

⇒ A = 4 × 11 × 11

⇒ A = 484

**∴ Amount received is Rs.484**