₹ $800$ at $5 \%$ per annum compound interest amounts to ₹ $882$ in how many years?

In what time (in $years$) will ₹ $8,000$ at $3 \%$ per annum produce the same interest as ₹ $6,000$ does in $5$ years at $4 \%$ simple interest?

Aditya invested a certain amount in two different schemes $A$ and $B$. Scheme $A$ offers $S.I.$ at $12$ $p.c.p.a.$ and scheme $B$ offers $C.I.$ at $10$ $p.c.p.a.$ The interest accrued on the amount invested in scheme $A$ in $2$ years was $Rs. 3600$ and the total amount invested was $Rs. 35000$. What was the interest accrued on the amount (in $Rs.$) invested in scheme $B$?

The simple interest on a sum of money for $3$ years is ₹ $240$ and the compound interest on the same sum,at the same rate for $2$ years is ₹ $170$. The rate of interest is (in $\%$):

If the amount is $6 \frac{1}{4}$ times the principal after $2$ years at compound interest,the rate of interest (in $\%$) per annum 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?