$A$ man runs around a circle of $50\, m$ radius at a speed of $12\, km/h$. Find the time taken by him for going around it ten times (in $minutes$).

The diameters of two concentric circles are $8\, cm$ and $10\, cm$. The area of the region between them is

The length of a rectangular plot of land is three times as much as its breadth. $A$ playground measuring $1200 \ ft^2$ occupies $\frac{1}{4}$ of the total area of the plot. What is the length of the plot in feet?

$A$ lawn is in the form of a rectangle having its breadth and length in the ratio $3:4$. The area of the lawn is $\frac{1}{12}$ hectare. The breadth of the lawn is..........$metres$.

In the given figure,$PQR$ is a triangle and quadrilateral $ABCD$ is inscribed in it. Given $QD = 2 \text{ cm}$,$QC = 5 \text{ cm}$,$CR = 3 \text{ cm}$,$BR = 4 \text{ cm}$,and $PB = 6 \text{ cm}$. What is the area (in $\text{cm}^2$) of the quadrilateral $ABCD$?

The area of the incircle of an equilateral triangle of side $42 \ cm$ is (in $cm^2$)