# MATHEMATICS IV

## Solutions Chapter 1 – Building with Bricks

#### Question 1:

• Which pattern is made in a circle?

• In which pattern can you show mirror halves? Draw a line.

• Now you draw some new floor patterns.

• Pattern given in figure J is made in circles. •

• Disclaimer: This answer may vary from student to student, based on his/her observation. It is highly recommended that the students prepare the answer on their own.

#### Question 1:

• How many faces in all does a brick have?

• Is any face a square?

• Draw the smallest face of the brick.

• A brick has 6 faces.

• No, all the faces of a brick are rectangular in shape..

• The smallest face of the brick is shown below:

#### Question 2:

Which of these are the faces of a brick? Mark a (✓).

#### Question 3:

Which of these is a drawing of a brick? Mark a (✓).

#### Question 4:

Make a drawing of this box to show 3 of its faces.

Figure of the geometry box showing 3 of its faces.

#### Question 5:

Can you make a drawing of a brick which shows 4 of its faces?

It is not possible to draw the figure of a brick that shows 4 of its faces.

#### Question 1:

Different Wall Patterns • Here are photos of three kinds of brick walls. Can you see the difference in the way the bricks are placed?

• Now match the photo of each wall with the correct drawing below:

Disclaimer: The arrangement of the bricks in all the three cases is different. The answer to this part of the question may vary from student to student.

#### Question 1:

How many different ‘jaali‘ patterns can you see in these two photos?

There are five different types of ‘jaali‘ patterns that can be seen in the above two photos.

#### Question 1:

Now colour some bricks red and make your own ‘jaali‘ patterns in the wall drawn below.

Disclaimer: The answer may vary from student to student, based on his/her observation. It is highly recommended that the students prepare the answer on their own.

#### Question 2:

Now draw some jharokha patterns on the wall here. You can shade it black.

Disclaimer: The answer may vary from student to student. It is highly recommended that the students prepare the answer on their own. The answer provided here is for reference only.

#### Question 1:

Where else have you seen an arch? ______________________

We can see  arches in rainbow, bridge, tunnel etc.

Disclaimer: The answer may vary from student to student. It is highly recommended that the students prepare the answer on their own. The answer provided here is for reference only.

#### Question 1:

• Which of these bricks have curved edges?

• How many faces do you see of the longest brick?

• Is there any brick which has more than six faces?

• Following are the bricks with curved edges:

• We can see only 1 face of the longest brick.

• No, there is no brick with more than 6 faces.

#### Question 2:

Take one brick and measure it. (a) How long is it? _____________________ (b) How wide is it? _____________________ (c) How high is it? _____________________

(a) 21 cm

(b) 10 cm

(c) 0.7 cm

Disclaimer: The answer may vary from student to student. It is highly recommended that the students prepare the answer on their own. The answers provided here are for reference only.

#### Question 3:

Muniya wants to make a wall 1 metre long. How many bricks will she need to put in a line? _______________

Let the length of each brick be 10 cm. Length of wall = 1 m As the length of brick in cm, the length of the wall will be converted to cm for calculation. We know that 1 m = 100 cm Length of wall (in cm) = 1

×100 cm = 100 cm Number of bricks required to make a 100 cm long wall = Length of wall

÷Length of 1 brick = 100

÷10 = 10 The number of bricks required to make 1 m long wall = 10.

Disclaimer: The answer may vary from student to student, based on his/her observation. It is highly recommended that the students prepare the answer on their own. The answer provided here is for reference only.

#### Question 4:

Can you guess how high is the chimney here? Is it: (a) about 5 metres? (b) about 15 metres? (c) about 50 metres?

The chimney shown in the picture is about 50 metres high.

#### Question 1:

Here are four pictures from the brick kiln. These pictures are jumbled up. Look at them carefully.

Write the correct order. __________________

The correct order is C, D, B, A.

#### Question 1:

Mental Math: Bhajan Buys Bricks Bhajan went to buy bricks. The price was given for one thousand bricks. The prices were also different for different types of bricks.

 Old bricks – Rs 1200 for one thousand bricks New bricks from Intapur – Rs 1800 for one thousand bricks New bricks from Brickabad – Rs 2000 for one thousand bricks

Bhajan decided to buy the new bricks from Brickabad. He bought three thousand bricks. How much did he pay? _______________

• Guess what he will pay if he buys 500 old bricks.

Bhajan bought new bricks from Brickabad. Cost of one new brick from Brickabad = Rs 2000

÷1000 = Rs 2 Cost of 3000 new bricks bought from Brickabad = Rs 2

×3000 = Rs 6000

• Bhajan bought 500 old bricks and the cost of 1000 old bricks = Rs 1200 We have to find the cost of 500 old bricks, which is half of 1000 bricks. Cost of 500 old bricks = Rs 1200

÷2 = Rs 600 Thus, the cost of 500 old bricks = Rs 600