Question : Diagonals of a trapezium $ABCD$ with $AB \parallel CD$ intersect each other at the point $O$. If $AB = 2CD$, then the ratio of the areas of $\triangle AOB$ and $\triangle COD$ is:

Question : In a trapezium ABCD, AB and DC are parallel sides and $\angle ADC=90^\circ$. If AB = 15 cm, CD = 40 cm and diagonal AC = 41 cm, then the area of the trapezium ABCD is:

Question : If $\triangle A B C \sim \triangle D E F$, and $B C=4 \mathrm{~cm}, E F=5 \mathrm{~cm}$ and the area of triangle $A B C=80 \mathrm{~cm}^2$, then the area of the $\triangle DEF$ is:

Question : The parallel sides of a trapezium are $8\;\mathrm{cm}$ and $4\;\mathrm{cm}$. If the $\mathrm{M}$ and $\mathrm{N}$ are the mid-points of the diagonals of the trapezium, then the length of $\mathrm{MN}$ is:

Question : The centroid of a $\triangle ABC$ is G. The area of $\triangle ABC$ is 60 cm². The area of $\triangle GBC$ is: