The difference between simple interest and compound interest on a certain sum for $3$ years at $5 \%$ per annum is ₹ $122$. Find the sum (in ₹).

There is a $60 \%$ increase in an amount in $6$ years at simple interest. What will be the compound interest (in $Rs.$) on $Rs. 12,000$ after $3$ years at the same rate?

An amount of ₹ $12500$ is deposited for a period of $2$ years at an interest rate of $4 \%$ per annum. Find the difference between the simple interest and the compound interest (in ₹) for the deposit.

$A$ sum of ₹ $3,200$ invested at $10 \%$ per annum compounded quarterly amounts to ₹ $3,362$. Compute the time period (in years).

The difference between simple and compound interest on a sum of $10000$ is $64$ for $2$ years. Find the rate of interest. (in $\%$)

Mr. Dua invested money in two schemes $A$ and $B$ offering compound interest at $8 \%$ per annum and $9 \%$ per annum respectively. If the total amount of interest accrued through two schemes together in two years was ₹ $4818.30$ and the total amount invested was ₹ $27000$. What was the amount (in ₹) invested in scheme $A$?