$A$ tree increases annually by $\frac{1}{8}$ of its height. By how much will it increase (in $cm$) after $2$ years,if it stands today $64 \ cm$ high?

The $S.I.$ is $Rs. 7200$ at $12$ $p.c.p.a.$ for $6$ years on a sum. What is the $C.I.$ (in $Rs.$) on the same sum at $5$ $p.c.p.a.$ for $2$ years?

The compound interest on a certain sum for $2$ years at $10 \%$ per annum is ₹ $525$. The simple interest (in ₹) on the same sum for double the time at half the rate per cent per annum is

The simple interest on a certain sum of money for $3$ years at $8 \%$ per annum is half the compound interest on ₹ $4000$ for $2$ years at $10 \%$ per annum. The sum placed on simple interest (in ₹) is

The difference between the simple interest and the compound interest (in ₹) on ₹ $600$ for $1$ year at $10 \%$ per annum,reckoned half-yearly is

In a certain number of years,a sum of money doubles itself at $6 \frac{1}{4} \%$ simple interest per annum. The required time (in $years$) is: