Find the difference between $C.I.$ and $S.I.$ on $Rs. 15000$ at $3 \%$ per annum for $3$ years.

The simple interest accrued on an amount of $Rs. 19800$ at the end of $3$ years is $Rs. 7128$. What would be the compound interest (in $Rs.$) accrued on the same amount at the same rate in the same period?

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 $A$?

$A$ bank offers $5 \%$ compound interest calculated on a half-yearly basis. $A$ customer deposits ₹ $1600$ each on $1^{st}$ January and $1^{st}$ July of a year. At the end of the year,the amount (in ₹) he would have gained by way of interest is

In how many years will ₹ $2,000$ yield ₹ $662$ as compound interest at $10 \%$ per annum compounded annually?

There is a $60 \%$ increase in an amount in $6$ years at simple interest. What will be the compound interest (in ₹) of ₹ $12000$ after $3$ years at the same rate?