$A$ room $5\, m \times 8\, m$ is to be carpeted leaving a margin of $10\, cm$ from each wall. If the cost of the carpet is ₹ $18$ per $m^2$,then the cost of carpeting the room will be (in $Rs.$)

The area of a parallelogram is $72 \, cm^{2}$ and its altitude is twice the corresponding base. The length of the base is.....$cm$.

The smallest side of a right-angled triangle is $8\, cm$ less than the side of a square of perimeter $56\, cm$. The second largest side of the right-angled triangle is $4\, cm$ less than the length of the rectangle of area $96\, cm^2$ and breadth $8\, cm$. What is the largest side of the right-angled triangle? (in $cm$)

The areas of a square and a rectangle are equal. The length of the rectangle is greater than the side of the square by $5 \text{ cm}$ and the breadth is less than the side of the square by $3 \text{ cm}$. Find the perimeter of the rectangle (in $\text{cm}$).

In the figure,$DE \parallel BC$. If $DE = 3 \text{ cm}$,$BC = 6 \text{ cm}$,and the area of $\Delta ADE = 15 \text{ cm}^2$,then the area of $\Delta ABC$ is ............ $\text{cm}^2$.

Three equal cubes are placed adjacently in a row. Find the ratio of the total surface area of the new cuboid to the sum of the surface areas of the three cubes.