$A$ certain sum of money at compound interest grows up to ₹ $12960$ in $2$ years and up to ₹ $13176$ in $3$ years. Find the rate per cent per annum.

The compound interest on a certain sum of money for $2$ years at $5 \%$ per annum is ₹ $410$. The simple interest (in ₹) on the same sum at the same rate and for the same time is:

On a sum of money,the simple interest for $2$ years is ₹ $660$,while the compound interest is ₹ $696.30$,the rate of interest being the same in both the cases. The rate of interest (in $\%$) is

$A$ man borrows $Rs. 5100$ to be paid back with compound interest at the rate of $4 \%$ p.a. by the end of $2$ years in two equal yearly instalments. How much (in $Rs.$) will be each instalment?

The difference between compound and simple interest at a certain rate on $Rs. 2000$ at the end of two years is $Rs. 12.8$. The rate of interest (in $\%$) per annum is:

Aditya invests $Rs. 50,000$ in a fixed deposit at $10 \%$ $C.I.$ for $2$ years. At the end of $2$ years,she puts the money in another deposit at $12 \%$ $S.I.$ for $3$ years. What was the final value (in $Rs.$) of the initial investment?