A person invests in the stock market at 10% per annum, compounded annually, for 1 years. If the interest was compounded half-yearly, he would have received Tk. 75 more. Find the sum that invest in the stock market.

When interest compounded annually, then person get 10% of the total sum
If interest compounded half-annually,
Interest rate = 5% and time t = 2

As we know, 5 + 5 + (5 × 5)/100 = 10.25%
If interest compounded half-annually, then person get 10.25% of the total sum

According to the question
⇒ 10.25% – 10% = 75
⇒ 0.25% = 75
⇒ 100% = 30,000

∴ The sum that invest in the stock market = Tk. 30000