Eka: Zzero ! Will you stop bouncing around like this, please?
Zzero: I’m happy. So I’m bouncing. I can take on so many shapes.

Eka: Stop boasting. Do you know how many numbers you can make up? 0, 10s, 100s, 1,000s and 10,000s. That’s a lot of numbers. 0, 10, 20, 30, ….90, 100, 101, 110, 200, 201, 210, ….

Zzero: Please stop! I want to find out how many numbers exist between 0 and 10,000 with one or more zeroes in them. The first one is 0 and the last is 10,000 so that makes two…

Eka: Zzero, hats off to you for saying you will take up such a BIG challenge. I think you should first try to find out how many numbers have one or more zeroes between 0 and 1,000.

Readers, can you help us please?

Acharya Vinoba Bhave was a freedom fighter. He followed the teachings of Mahatma Gandhi and lived between the years 1895 and 1982.

When he was a young boy in Maharashtra, his mother had made a vow of offering 10,000 grains of rice to God. She carefully counted a hundred grains each day and offered it in prayer, reciting God’s name each time she made an offering.

Vinoba’s elder brother had an idea. He said, “Mother, why do you do this everyday? After counting a hundred grains on one day, measure its weight. From the next day, you just have to weigh out an equal amount and offer it to God. This will save you time and effort.”

Vinoba said, “I don’t think that would be right. When you count 100 grains of rice each day, you will repeat God’s name 100 times. But if you weigh out 100 grains, you would say God’s name only once!”

Sankhya’s mother was getting ready to go to school. She was a geography teacher. “Sankkima, eat your breakfast quickly!” she shouted.

“Ki-ki, have you finished your homework?” asked Sankhya’s father.

“S V!” yelled Sankhya’s friend Manjula from the street. Sankhya’s father’s name is Venkat.

“I have a million names!” said Sankhya with a grin, as she got ready to eat her breakfast.

Sankhya answers to all the different names she is called by. Numbers too are like Sankhya. They have different names in different countries.

1,000 x 1,000 = 1,000,000. Thousand 1,000s make a million. In India, we say 10 lakhs instead of one million.


100 x 100,000 = 10,000,000. One hundred lakhs is called one crore in India.


1,000 x 1,000,000 = 1,000,000,000. In America, 1,000 millions are called a billion.


1,000 x 1,000 x 1,000,000 = 1,000,000,000,000. And a billion is a thousand thousand million in all countries except the United States of America.


Surprisingly, scientists, whether in India or America mean 1,000 million when they say billion.

When someone asks you how far your school is from your house you may say, “Very far.”

To a stranger asking for directions to the school, you would probably say, “Five kilometres, Sir.”

The Sun is 300,000 times heavier than the Earth. To write the mass of the Sun in tonnes you need to write 2 followed by 27 zeroes.

Numbers help us to understand the world around us better.

Scientists say the universe was formed because of a ‘Big Bang’.

15 billion years ago there was a small super hot, super dense, ball of fire.

The ball was less than 1cm wide. Suddenly, the ball exploded.

The ball was less than 1cm wide. Suddenly, the ball exploded.

In less then a millionth of a second, it grew to a huge ball, 16 billion km across.

In the next million years, the exploded pieces became colder and formed galaxies.


The Earth, Moon and Sun belong to a galaxy called the Milky Way.

They were born less than 5 billion years ago.

There are 200 billion stars in our galaxy.

Our Sun is one of them. Earth is one of the nine planets moving around our Sun

And the Earth has 6,525,170,264 people.

You are one of 1,095,351,995 people living in India!

The Principal of Aryanagar Vidyamandir is very strict. He insists that students stand in their specified places during morning assembly.

Ranjit, a class 4 student, always stood in the fourth row from the right side of the hall.

One day, he got into the sixth row, where all the Class 6 students stood. He felt very important. He also felt very scared that the principal would seek him out and punish him.

The principal did find out and called Ranjit to his room. “Young fellow, so you don’t want to stand in your place, is it?

If you want to stand in the Class 6 row, you have to increase your value by studying well and learning well to deserve the value of being in the Class 6 row. Understand? Now, run to class!”

Ranjit scratched his head, and walked back to his class. What was his value, he wondered.

He had learnt place value in arithmetic recently and this is what he understood about value. The digit 2 means just 2.
When you write 20, the 2 indicates there are 2 tens.

Similarly when you write 2032, the 2 on your right denotes just 2 but the 2 on your left means there are 2 thousands.
So, depending upon the ‘place’ where a digit sits, it gets different values.

Let’s take the number 167,234. Each digit here has a different place value. 1 is in the lakh’s place. In the number 167,234, the place value of 1 is one lakh. 6 is in the ten-thousand’s place. The place value of 6 in 167,234 is 60,000. A number is the sum of the place values of its digits. 100000+60000+7000+200+30+4=167234 100000 60000 7000 200 30 4 167234 . Ranjit has understood place value quite well now.

Zzero, do you know how to multiply with your fingers?

Of course. I pick up a pencil and paper with my fingers, write the numbers and then write the answers.

No, silly, I meant with only your fingers. See, here’s how you multiply by 9 with your ten fingers.

Multiplication is a quick way of adding.

Suppose you pluck 25 mangoes from one tree in an orchard, and your grandmother has asked you to get 250 mangoes to make spicy mango pickles, you do not have to keep count after plucking every mango.

Just pluck 25 mangoes from each tree. Leave them in separate baskets at the foot of the tree.

One basket contains 25 mangoes. 2 Baskets will contain 25+25=50 25 25 50 mangoes. You can just multiply 25 by 2 instead. 25×2=50 25 2 50 . 3 baskets x 25 mangoes in each = 3×25=75 3 25 75 . 10 baskets x 25 mangoes in each = 10×25=250 10 25 250 .

When the numbers to be multiplied are small, it is easy to add repeatedly. But when numbers are big, it is easier to multiply.

An old man lived by the river Kaveri.

He used to catch fish for a living. But he did not eat fish himself.

Everyday he caught fish and sold them in the evening at the market.

He was not a greedy man.

One day his grandson saw him throwing back a fish into the river. “Grandpa, why did you do that?” he asked.

“Little one, I need to earn, so I catch fish. But I don’t need too much money. So I put back some fish into the river.”

“And how do you decide which fish to put into the basket and which fish to throw back into the river?”

“Each day, I make up a rule for myself. Yesterday, I threw back the first fish I caught, kept the second, threw back the third, kept the fourth…”

“I know, you threw back Fish 1, Fish 3, Fish 5………..You threw back the Odd-numbered fish!”

“That’s right. Today, I kept the first fish, threw back the second, kept the third, threw back the fourth…”

“All the even-numbered ones went back into the river. Poor odd-numbered ones!”

“Tomorrow, I’m going to need a little more money. So I’ll have a new system. Fish numbers 2, 3, 5, 7, 11, 13, 17, 19, 23, and so on will go back into the river. The rest will get into my basket.

“Grandpa, how many fishes do you sell each day?”
“About 50.”

1 is an odd number. 2 is an even number.

Numbers that cannot be divided by 2 are called odd numbers.

Numbers that can be divided by 2 are called even numbers.

Eka, have you seen the Hindi film ‘Sholay’?

There is a scene in the movie that has a jailer telling his officers,

“Half of you go this side. Half of you go that side. Rest of you, follow me!”

Zzero:Tell me Eka, how many people followed the jailer?
Eka:Zzero, you must be joking!

Zzero:No one followed the jailer. One half plus another half of the same thing makes a full!

Sankhya and Ganith had to share a huge aloo Paratha for lunch. They both liked aloo Paratha very much. “Let’s cut it into two. Each of us can have one part,” said Ganith. “You cut it, Sankhya.”

Sankhya was going to fold the paratha into two, when her friends Faisal and John walked in. “We want a piece too!” they said.

Sankhya and Ganith would have had 12 1 2 a paratha each. Now they would have to have 14 1 4 of a paratha.

So they had to divide one paratha into four equal pieces. After Sankhya had cut the paratha neatly into four pieces, John saw a sugarcane piece in the kitchen. “I’ll eat the sugarcane. I don’t want the paratha,” he decided.

Sankhya, Ganith and Faisal had a quarter of the paratha each. And they cut up John’s quarter into three. What do you think they did with that!

Sankhya watched as Amma made a beautiful rangoli. First she made many dots. Then she joined the dots to make designs.

“Amma. How do you know how many dots to make?”

Amma mumbled something, because she really did not have an answer.

But Zzero has discovered a way to make shapes out of numbers.

Take any number and its next number. (Two numbers that have a difference of 1 are called consecutive numbers.)

Multiply them and divide the answer by 2.

You can make a triangular number grid with this new answer.

6×7 6 7 divided by 2 = 21.

You can form a triangle with 21 dots, starting with 6 dots at the bottom, reducing one dot as you go higher, till you have just one dot on top.

Or you can start with one dot on top, and keep increasing one dot in the next line as you go down.

Zzero: Eka, let’s fly!
Eka: Zzero, we are not birds. And we are not pilots. So how can we fly?

Zzero: Let’s make paper planes and fly them. Listen friends, let’s play detectives!

Write a coded message using numbers on a piece of paper. Make this into a paper plane. Send it zooming in the class.

The person on whom the plane lands has to decode the message. The numbers must represent alphabets.

The numbers that make up one word can be put together with hyphens.

Some students scratched their heads.
Some scratched busily on papers with their pencils. Soon there were different kinds of planes flying in class.

Can you decode some of these messages that ‘landed’?

Sankhya and Ganith have made friends with numbers. Sometimes the ‘friends’ behave oddly! But most of the time, they are good! Look at the numbers around you. You may find something interesting about them.