direktori wisata tirta 2012 (13)

8/12/2019 Direktori Wisata Tirta 2012 (13)

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Dhaval Bathia


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Dhaval Bathia


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Dhaval Bathia

When we say multiplication with a

series of 1, we mean numbers like 1,11, 111, 1111 etc.

In this case, the multiplicand can beany number, but the multiplier has tobe a series of 1.


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Dhaval Bathia

First, let us see how to multiply numberswith 11

Q) Multiply 42 with 11

4 2x 1 1


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Dhaval Bathia

4 2x 1 1

First, we put the last number as it is. So number 2will come down as 2.

Next, we add both the numbers and put it in thecentre. So, (4+2) will be written as 6.

Finally, we put the first number as it is. So, 4 willcome as 4.

264

The final answer is 462


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Dhaval Bathia

6 3x 1 1

First, we put the last number as it is. So number 3will come down as 3.

Next, we add both the numbers and put it in thecentre. So, (6+3) will be written as 9.

Finally, we put the last number as it is. So, 4 willcome as 6.

396



7/15

Dhaval Bathia

Similarly when 35, 27 and 44 aremultiplied by 11, the answers will be :

3 5

x 1 1

2 7x 1 1

4 4x 1 1

3 8 5 2 9 7 4 8 4


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Dhaval Bathia

Sometimes, you may have a carry-over, let us seehow to deal with such cases:

Q) Multiply 48 with 11

4 8X 1 1


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Dhaval Bathia

4 8X 1 1

First, we put the last number as it is. So number 8 willcome down as 8.

Next, we add both the numbers and put it in the centre. So,(4+8) will be 12. We write down 2 and carry-over 1.

Finally, we put the last number as it is. So, 4 will comeas 4. But, since 1 is carried over, the answer is 5.

825



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Dhaval Bathia

Q) Multiply 5 4 3

x 1 1

Here, we will apply the same logic that we have usedin our previous examples

We put the last number as it is (Answer - _______3)

We add 4 +3 and write down 7 (Answer - _______73)

We add 5 + 4 and write down 9 (Answer - _____973)

We put the first number as it is i.e. 5


5 9 7 3


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Dhaval Bathia

We have seen how to multiply numbers with 11,next, we will see how to multiply numbers with 111

In the number 11, the number 1 appears twice,so we will add maximum two digits at a time. Inthe number 111, the number 1 appears thrice,

so we will add 3 digits at a time


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Dhaval Bathia

2 0 3

x

1 1 1

Write the last number as it is. (one digit)

Next, we add 0 + 3 and get 3. ( two digits)

Next, we add 2+0+3 and get 5 (three digits = maximum)

Next, we add 2+0 and get 2 (two digits)

Finally, we put the first number (2) as it is(one digit)

The final answer will be 22533

2 2 5 3 3


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Dhaval Bathia

4 3 5

x

1 1 1

Write the last number as it is. (one digit)

Next, we add 3 + 5 and get 8. ( two digits)

Next, we add 4+3+5 and get 12 (write 2, carry over 1)

Next, we add 4+3 (plus 1 carried over) and get 8 Finally, we put the first number (4) as it is(one digit)

The final answer will be 48285

4 8 2 8 5


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Dhaval Bathia

Similarly,

111 90321 6021203

x 111 x 111 x 111

12321 10025631 668353533


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Dhaval Bathia

Using the same method, we can multiply a number withany number of 1s

If you want to multiply a number with 1111, you will usethe same technique. The only difference will be thatyou will add maximum four digits at a time (because

there are four ones in 1111)

When the multiplier is 11111, we will be adding

maximum five- digits at a time

direktori wisata tirta 2012 (13)

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