$A$ rectangular field costs $Rs. 110$ for levelling at $50$ $paise$ per square metre. If the ratio of length to breadth is $11: 5$, find the length of the field (in $m$).

$2$ small circular parks of diameters $16 \ m$ and $12 \ m$ are to be replaced by a bigger circular park. What would be the radius of this new park,if the new park occupies the same space as the two small parks?

The area of a right-angled triangle with base $6\,m$ and hypotenuse $6.5\,m$ is........$m^2$

The ratio of the area of the incircle and circumcircle of a square is?

The length of a rectangle is increased by $60 \%$. By what percent would the width have to be decreased so as to maintain the same area?

$\Delta ABC$ is similar to $\Delta PQR$. The length of $AB$ is $16 \ cm$ and the length of the corresponding side $PQ$ is $9 \ cm$. If the area of $\Delta ABC$ is $1024 \ cm^2$,what is the area of $\Delta PQR$ in $cm^2$?