Bài 16: Multiplying a two digit by a one digit number

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Starry isn’t multiplication a really long word?

Specially when you have to learnt the spelling m-u-l-t-i-p-l-i-c-a-t-i-o-n.

But Starry, I can show you an easy way to learn the spelling simply break up the word multiplication into smaller word like multi-pli-cat-ion

Wasn’t that easy?

 Now we can do something similar when we have to multiply a two digit number by a one digit number.

Suppose we have to multiply 43 by 2.

Let us first break up the number 43,
 43 means 40 and 3, right!
Next, multiply 40 by 2, 40 times 2 is 80.

Now multiply 3 by 2, 3 times 2 is 6.

Sum of 80 and 6 is 86.

So we have 43 multiply by 2 equals 86.

Let us try another one.
Multiply 32 by 3.

What should we do first Starry?

Right, the first break up the number 32.
So 32 means 30 plus 2.

Next, multiply 30 by 3, 30 times 3 is 90, multiply 2 by 3, 2 times 3 is 6. 90 and 6 is 96.
Hence, 32 multiply by 3 is 96.

I hope you understood Starry!

Let me see if you can help me out with this one.

34 multiply by 2.
Yes Starry, 34 can be broken up into 30 plus 4, multiply 30 by 2, 30 times 2 is 60.

Very good Starry!

Next, multiply 4 by 2,
 4 times 2 is 8. 
The sum of 60 and 8 is 68.

So, 34 multiply by 2 is 68.

Excellent Starry.

You have now learnt that it is possible to break up two digit number when you have to multiply them by one digit numbers.

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