Mensuration 2D

The ratio of heights of two cylinders is $3:2$and the ratio of their radii is $6:7$. What is the ratio of their curved surface areas?

The side of a square is $40 \mathrm{cm}$. If its sides increased by $25\%$, what will be a percent increase in its area?

The diameter of a wheel is $3 \mathrm{m}$. The wheel revolves $28$ times in a minute. To cover $5.280 \mathrm{km}$ distance, the wheel will take how much time? (Take $\pi =\frac{22}{7}$)

Two cones have their heights in the ratio $1 : 2$ and the diameters of their bases are in the ratio $2 : 1$. What will be the ratio of their volumes?

The perimeter of a square and a rectangle is$48$ m each. The differences between the areas of the two is $4$ m^$2$. The measurements of the rectangle (in metres) are

The ratio between the perimeter and the breadth of a rectangle is$5 : 1$. If the area of the rectangle is $216$ sq. cm, what is the length of the rectangle$?$

If the base radius and the height of a right circular cone are increased $40\%$, then find the net $\%$ increase in volume _____.

The area of a square is $441 {\mathrm{m}}^2$. It's side is equal to the radius of a circle. Find the circumference of the circle.

A playground is in the shape of a rectangle. A sum of $₹1000$ was spent to make the ground usable at the rate of$25 paise$ per square metre. The breadth of the ground is $50 metre$. If the length of the ground is increased by $20 metre$, what will be the expenditure in rupees at the same rate per square metre?

If the side of square is increased by 25%, then the area is increased by -

Find the area of a regular octagon whose side $10 cm.$

The length and perimeter of a rectangle are in the ratio $5 :18$.Then length and breadth will be in the ratio______.

The breath in area of rectangle is:

$\mathrm{ABCD}$ is a square where the length of a side is $10 \mathrm{cm}$. $\mathrm{OCD}$ is an isosceles triangle with base $\mathrm{CD}$. $\mathrm{OC}$ cuts $\mathrm{AB}$ at point $\mathrm{Q}$ and $\mathrm{OD}$ cuts $\mathrm{AB}$at point $\mathrm{P}$ . The area of the trapezoid $\mathrm{PQCD}$ is $80 {\mathrm{cm}}^2$. The altitude from $\mathrm{O}$ of the triangle $△\mathrm{OPQ}$is-

Two circles with centres $A$ and $B$ and radius $2 \mathrm{units}$ touch each other externally at $C$. A third circle with centre $C$ and radius $2 \mathrm{units}$ meets other two at $D\hspace{0.17em}\&\hspace{0.17em}E$. Then the area of the quadrilateral $ABDE$ is

The area of a rectangle whose one side is '$a$' is $2a^2$. What is the area of a square having one of the diagonals of the rectangle as side?

$∆ABC$ and $∆BDE$ are two equilateral triangles in such a way that $D$ is the midpoint of $BC$. Then $\mathrm{ar}(∆BDE) : \mathrm{ar}(∆ABC)=$?

A spherical lead ball of radius of $10 \mathrm{cm}$ is melted into radius of $5 \mathrm{mm}$ of small lead balls .The total number of possible small lead boll is -

If a right circular cone of height $24 \mathrm{cm}$ has a volume of $1232 {\mathrm{cm}}^3$, Then what will be the area of its curved surface? 

In the given figure, the ray will be named as ______.