Bài 13: Multiplying a one digit by a one digit number

Starry, I hope you remember the two different ways in which you can arrange digits when you have to multiply them.

One is a horizontal arrangement as it seen when you write on table.

So 3x4 are 12 is written as 3 multiply by 4 equal 12.

The same digits when written in the vertical arrangement will be 3 multiply by 4 equal 12.

Here Starry, both 3 and 4 are one digit numbers.

So we have just multiplying a 1 digit number by another 1 digit number.

Let me show you how.

First you places both 3 and 4 one below the other in the unit places.

Next, you see the 4 times table up to 4x3, 4x1 are 4, 4x2 are 8, 4x3 are 12.

Hence, the product is 12.

So we write 2 in the unit places and 1 in the ten places.

Wasn’t that easy Starry?

Now let try another set of 1 digit number.

Let us multiply 6 by 9.

We will see the 9 times table up to 9x6. So 9x6 are 54.

The product is 54.

We write 4 in the unit places and 5 in the ten places.

Now let me see if you have understood what I have just start you.

Let multiply using table.

In the first example, we see the 6 times table up to 6x3, so 6x3 are 18, the product is 18.

In this example, we see the 7 times table, 7x7 are 49, the product is 49.

Here we see the 9 times table, 9x5 are 45. The product is 45.

Now that you have understood multiplication, let me show you something interesting.

Look at this you have to help me fill the correct number in the boxes.

Let’s begin, we have to get the number 18 as the product, we will first see the 6 times table then we reach 18.

So 6x3 are 18.

The number that go into first box is 3.

But Starry I hope you remember that we get the same product when the multiplier and multiplication change places.

So 6 times 3 equal 3 times 6 is equal to 18 and the number in on next box should be 6.

Wasn’t that easy!

Here Starry, we have to get the number 12 ask the product in the different boxes.

We begin with the 3 times table, we reach 12, 3x4 are 12.

The number in the first box is 4.

But remember we kept the same product when the multiplier and multiplication change places.

So 3 times 4 equal 4 times 3 is equal 12.

Hence, it follow that the number in the second box will be 3.

We next see the 2 times table, then we reach 12, 2x6 are 12.

The number in the next box is 6.

2 times 6 equal 6 times 2 is equal 12.

And so the number in the last box has to be 2.

Let us now provide what we have learnt.

Here we have to get the number 36 as the product.

So let us fill the different boxes, we begin with the 4 times table.

4 times … is 36, 4x9 are 36.

So the number in the first box is 9.

4 times 9 equal 9 times …. equal 36.

9 times 4 equal 36.

The number in the second box should be 4.

And third and fourth box, we will see the 6 times table, we reach 36, 6 times ….is 36, 6x6 are 36 .

the number in the last box has to be 6.

Great Starry, you have finally understood how to multiply one digit numbers