NCERT solutions for Math - Magic [English] Class 5 chapter 14 - How Big? How Heavy? [Latest edition]

Mohan arranged his matchboxes like this.

• How many matchboxes did he use to make it? What is its volume in matchboxes? ________ matchboxes.

Now make a guess. Do you think the volume of 10 five-rupee coins will be more than that of 10 marbles?
Guess the volume of these:

• A ball is nearly _________ marbles.
• An eraser is nearly _________ marbles.
• A lemon is nearly __________ marbles.
• A pencil is nearly __________ marbles.
• A potato is nearly __________ marbles.

Now make your own measuring glass using 35 marbles.

Take a glass of water and mark the level of the water as 0. Then put in 5 marbles and mark the level of the water as 5 M.

Again drop 5 marbles and mark the level of the water as 10 M. Likewise make the markings for 15 M, 20 M, 25 M, 30 M, and 35 M.

Now put each thing in the measuring glass and check your guess.

Try with different things like a matchbox, a stone, etc., and fill the table.

Use your measuring bottle to find out:

• What is the volume of 6 marbles? ________ mL.

Use your measuring bottle to find out:

• What is the volume of 16 one-rupee coins? _________ mL.

Use your measuring bottle to find out:

• The volume of 24 marbles is _________ mL.

Use your measuring bottle to find out:

• The volume of 32 one-rupee coins? _________ mL.

Use your measuring bottle to find out:

Mollie puts some five-rupee coins in the measuring bottle. How many coins has she put in it:

• if 30 mL water is pushed up?
• if 60 mL water is pushed up?

First guess and then use your measuring bottle to find out the volume in mL of some other things.

Guess how many litres of water your body will push up?!

Hey, my math-magic book is about ___ cm long. So______ cubes will fit along its length. 

And it is about ______ cm wide. So ______ cubes will fit along the width.

So total ______ cm cubes will fit n the Math-Magic book.

Now if all these cubes are arranged in one line then how long will that line be?______cm

A stage (platform) is made with 5 Math-Magic books. The volume of this stage is the same as ______ cm cubes.

Guess the volume of these things in cm cubes.

• A matchbox is about __________ cm cubes.

Guess the volume of these things in cm cubes.

• A geometry box is about _________ cm cubes.

Guess the volume of these things in cm cubes.

• An eraser is about __________ cm cubes.

Tanu is making a stage with matchboxes.
She first puts 14 matchboxes like this in the first layer.

She makes 4 such layers and her stage looks like this.

• She used ________ matchboxes to make this stage.

Tanu is making a stage with matchboxes.
She first puts 14 matchboxes like this in the first layer.

She makes 4 such layers and her stage looks like this.

• The volume of one matchbox is the same as 10 cm cubes. Then the volume of this stage is the same as ________ cm cubes.

Tanu is making a stage with matchboxes.
She first puts 14 matchboxes like this in the first layer.

She makes 4 such layers and her stage looks like this.

• If all these cubes are arranged in a line, how long will that line be? _________ cm.

Tanu is making a stage with matchboxes.
She first puts 14 matchboxes like this in the first layer.

She makes 4 such layers and her stage looks like this.

• Which has more volume — your Math-Magic book or Tanu’s platform?

Tanu is making a stage with matchboxes.
She first puts 14 matchboxes like this in the first layer.

She makes 4 such layers and her stage looks like this

• Use 56 matchboxes to make platforms of different heights. Fill this table.

The volume of each platform is equal to ________matchboxes.

Make deep drawings of the platforms you have made

Mohan arranged his matchboxes like this.

• How many matchboxes did he use to make it? What is its volume in matchboxes? ________ matchboxes.
• Collect empty matchboxes. Arrange them in an interesting way. Make a deep drawing of it.

How long is the side of your cube? ______

How many centimetre cubes can be arranged along its:

Length? ______

Width? ______

Height? ______

Answer Thimpu's questions:

• To make the first layer on the table how many cm cubes will I use? ______
• How many such layers will I need to make a cube? ______

So the total cm cubes = ______

The volume of the paper cube is same as __________ cm cubes.

Anan made a big cube having double the side of your paper cube. How many of your paper cubes will fit in it? Try doing it by collecting all the cubes made in your class.

Ganesh and Dinga want to pack 4000-centimeter cubes inboxes. These are to be sent to a school. There are three different boxes available for packing.

• What is your guess? Who is right?

Ganesh and Dinga want to pack 4000-centimeter cubes inboxes. These are to be sent to a school. There are three different boxes available for packing.

• How can Ganesh and Dinga test their guesses before packing the cubes in the boxes? Discuss with your friend.

Ganesh and Dinga want to pack 4000-centimeter cubes inboxes. These are to be sent to a school. There are three different boxes available for packing.

Use Ganesh's method and write:

• _____ centimeter cubes can be arranged in box B.
• _____ centimeter cubes can be arranged in box C.
• So _____ centimeter cubes in all can be packed in the three boxes.

Collect some old postcards. You can also use thick paper of size 14 cm x 9 cm.
Fold the postcard along the width to make pipe 1. Join the ends with cello tape.
Take another postcard and fold it along the length to make pipe 2. Join the ends with tape.

• Guess which pipe can take more sand inside it. Hold it on a plate and pour sand to check your guess. Was your guess correct? Discuss.

The students of Class XII are going on a trek to Gangotri. They have to pack their bags for six days and keep them light. They also have to take things that do not take too much space. So they will look for things that have both less volume and less weight. After all, they will carry their own bags while climbing the mountains!

They even dry the onions and tomatoes to make them light. One kg of onions or tomatoes becomes 100 g when the water inside dries up.

The list of food each person will need for one day:

For 6 days, each person will need

• Rice and flour − __________ g
• Pulses − _________ g
• Dried onions − _________ g

How much of fresh tomatoes should be dried for 6 days for 10 people?

What is the total weight of food (for 6 days) in each person s bag?

Guess how many children of your weight will be equal to the weight of an elephant of 5000 kg.

At birth, a baby elephant weighs around 90 kg. How much did you weigh when you were born? Find out. How many times is a baby elephant heavier than you were at birth?

If a grown-up elephant eats 136 kg of food in a day then it will eat around _________ kg in a month.

How many coins are there in a sack of 5 rupee coins if it weighs:

• 18 kg? ______

How many coins are there in a sack of 5 rupee coins if it weighs:

• 1 kg and 125 g? ______

How many coins are there in a sack of 5 rupee coins if it weighs:

• 2 kg and 250 g? ______

How many coins are there in a sack of 5 rupee coins if it weighs:

• 4500 g? ______

How many coins are there in a sack of 5 rupee coins if it weighs:

• 54 kg? ______

A 2 rupee coin weighs 6 g. What is the weight of a sack with:

• 2200 coins? _____ kg _____ g

A 2 rupee coin weighs 6 g. What is the weight of a sack with:

• 3000 coins? _____ kg

If 100 one rupee coins weigh 485 g then how much will 10000 coins weigh? _____ kg _____ g

How do people who cannot see make out different notes and coins? (Hint: Look for a shape etc. on notes of Rs 20, 50, 100, 500 etc. and feel it.)

What should we look for to check if a 100-rupee note is real or fake?