An error of $2 \%$ in excess is made while measuring the side of a square. The percentage of error in the calculated area of the square is.....$\%$

If the curved surface area of a cone is thrice that of another cone and the slant height of the second cone is thrice that of the first,find the ratio of the area of their bases. (in $:1$)

One of the diagonals of a rhombus is double the other diagonal. Its area is $25\, cm^{2}$. The sum of the diagonals is.......$cm$

In the given figure,there is a large semicircle with diameter $AB = 56 \ cm$. Inside this,there are four smaller identical semicircles with diameters $AE, EF, FG,$ and $GB$ along the diameter $AB$. $A$ circle is inscribed such that it is tangent to the large semicircle and the two middle smaller semicircles. What is the area (in $cm^2$) of the shaded region?

The area of a right-angled triangle with base $6\,m$ and hypotenuse $6.5\,m$ is........$m^2$

$A$ 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 $Rs.$)