$ABCD$ is a trapezium in which $AB \parallel CD$ and $AB = 2CD$. If its diagonals intersect each other at $O$,the ratio of the area of triangle $AOB$ and $COD$ is

$2$ 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?

If the area of an equilateral triangle is equal to the area of an isosceles triangle whose base and equal sides are $16 \, cm$ and $10 \, cm$ respectively,then the side of the equilateral triangle is......$cm$

The lengths of three medians of a triangle are $9 \, cm$,$12 \, cm$,and $15 \, cm$. The area (in $cm^2$) of the triangle is

$A$ rectangular carpet has an area of $60 \, m^{2}$. Its diagonal and longer side together equal $5$ times the shorter side. The length of the carpet is.........$m$

The side of a square exceeds the side of another square by $4\, cm$ and the sum of the areas of the two squares is $400\, cm^2$. The dimensions of the squares are?