Area of Irregular Shapes

Q.

Question 4

Find the missing values:

$$\begin{array}{ccc}Base& Height& Areaoftriangle\\ 15cm& \dots & 87c{m}^2\\ \dots & 31.4mm& 1256m{m}^2\\ 22cm& \dots & 170.5c{m}^2\end{array}$$

Q. Area of an irregular shape can be measured accurately using graph paper.

1. True
2. False

Q.

Describe a method to measure the area of an irregular shape?

Q.

Write the algebraic expression for the volume of a cube, if its side (a) is reduced by 5.

1. (a+5)³

2. (a³-5)

3. (a-5)³

4. (a-5³)

Q. Points to be followed while calculating the area of a figure using squared paper.

1. Ignore portions of area that are less than half a square.
2. If more than half a square is in the region, count it as one square.
3. If exactly half the square is covered, take its area as half sq. units.
4. If more than half a square is in the region, count it as half sq. units.

Q.

The figure given below is divided into 8 equal squares. If the side length of each small square is 1 m, find the area of the shaded region.

1. $8m^2$

2. $1m^2$

3. $6m^2$

4. $2m^2$

Q. What is the length of a side of a square whose area is 100 sq cm?

1. 10 cm
2. 10 sq cm
3. 20 cm
4. 20 sq cm

Q. The base of a right triangle is 15 cm and its hypotenuse is 25 cm. Then its area is :

1. $187.5c{m}^2$
2. $375c{m}^2$
3. $150c{m}^2$
4. $300c{m}^2$

Q.

A big rubik's cube is made whose dimension is $20\times 20\times 20$. Find the diffrence in volume of the bigger one and a smaller one whose dimension is $19\times 19\times 19$. [2 MARKS]

Q. Find the perimeter of the isosceles right angled triangle shown in the above figure if the length of its hypotenuse is given to be equal to $8\sqrt{2}$.

1. 8
2. $8+16\sqrt{2}$
3. 16
4. $8+8\sqrt{2}$
5. $16+8\sqrt{2}$

Q. Find the area of the given figure (all dimensions are in cm).

1. $46c{m}^2$
2. $36c{m}^2$
3. $63c{m}^2$
4. $60c{m}^2$

Q.

Find the area of figure given below (in sq. inches).

1. 48
2. 64
3. 84
4. 96

Q. Find the area of the given figure (all dimensions are in cm).

1. $46c{m}^2$
2. $36c{m}^2$
3. $60c{m}^2$
4. $63c{m}^2$

Q.

In the figure below, if DE = 2DC and the area of parallelogram ABCD = 20 square units, find the area of $\Delta DBC$ (in square units).

1. 5

2. 10

3. 4

4. 6