The difference of compound interest (in ₹) on ₹ $800$ for $1$ year at $20 \%$ per annum when compounded half-yearly and quarterly is:

$A$ sum of money at compound interest amounts to thrice itself in $3$ years. In how many years will it be $9$ times itself?

The compound interest earned by Shivam on a certain amount at the end of $2$ years at the rate of $8 \, p.c.p.a.$ was $Rs. 1414.4$. What was the total amount that Shivam got back at the end of $2$ years in the form of principal plus interest earned (in $Rs.$) (in $.4$)?

The difference between $C.I.$ and $S.I.$ on $Rs. 700$ in $2$ years at $5 \%$ per annum is (in $Rs.$):

Albert invested an amount of ₹ $8000$ in a fixed deposit scheme for $2$ years at a compound interest rate of $5 \%$ per annum. How much amount (in ₹) will Albert get on maturity of the fixed deposit?

$A$ man borrows money at $3 \%$ per annum interest payable yearly and lends it immediately at $5 \%$ interest (compound) payable half-yearly and thereby gains ₹ $330$ at the end of the year. The sum borrowed (in ₹) is