Two minor sectors of two distinct circles have the measure of the angle at the centre equal. If the ratio of their areas is $4: 9,$ then ratio of the radii of the circles is ........
$4:9$
$1:3$
$2:3$
$16:81$
The central angles of two sectors of circles of radii $7 \,cm$ and $21\, cm$ are respectively $120^{\circ}$ and $40^{\circ}$. Find the areas of the two sectors as well as the lengths of the corresponding arcs. What do you observe?
The ratio of areas of two circles is $25: 36 .$ Then, the ratio of their circumferences is.........
In a circle with centre $O, \overline{O A}$ and $\overline{O B}$ are radii perpendicular to each other. The perimeter of the sector formed by these radii is $75\, cm$. Find the area of the corresponding minor segment. (in $cm^2$)
It is proposed to build a single circular park equal in area to the sum of areas of two circular parks of diameters $16\, m$ and $12 \,m$ in a locality. The radius of the new park would be (in $m$)
The area of a minor sector of $\odot( P , 30)$ is $300 \,cm ^{2} .$ The length of the arc corresponding to it is ...........$cm .$