To calculate the balance after 4 years, we can break it down into two parts: the first two years and the next two years.
For the first two years, the interest is compounded annually at a rate of 6%. To calculate the balance after two years, we can use the formula:
Balance after 2 years = Principal * (1 + Rate/100)^Time
In this case, the principal is Rs 85,000, the rate is 6%, and the time is 2 years.
For the next two years, the interest is compounded quarterly at a rate of 11%. To calculate the balance after two years, we can use the same formula, but with a quarterly compounding period:
Balance after 2 years = Principal * (1 + Rate/100/4)^(Time*4)
In this case, the principal is the balance after the first two years, the rate is 11%, and the time is 2 years.
By calculating the balance after the first two years and then using that as the principal for the next two years, you can find the final balance after 4 years.
