Example-1

First we will take two digit number as an example to understand the concept:

STEP 1 :

First we will take a two VALUES like :

VALUE1 = '25'

VALUE2 = '27'

STEP 2 :

Now we will multiply unit place digit from both numbers like-

25

27

'5 * 7 = 35'

Result -

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if we have reminder like 3 then we will add that value in next calulation.

STEP 3 :

Now we will cross multiply the values like

25

27

'2 * 7 = 14 and 5 * 2 = 10' and add the result of multiplication '14 + 10 + 3 = 27'.
Result -

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if we have reminder like 2 then we will add that value in next calulation.

STEP 4 :

Now we will multiply tans place digit from both numbers like-

25

27

'2 * 2 = 4' and add reminder from previous calculation like '4 + 2 = 6'
Result -

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Example-2

we will take three digit number as an example to understand the concept:

STEP 1 :

First we will take a two VALUES like :

VALUE1 = '802'

VALUE2 = '232'

STEP 2 :

Now we will multiply unit place digit from both numbers like-

802

232

'2 * 2 = 4'
Result -

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if we have reminder like 0 then we will add that value in next calulation.

STEP 3 :

now we will cross multiply two digits and then add the values and also add previous reminder

802

232

'0 * 2 + 2 * 3 = 6'
Result -

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if we have reminder like 0 then we will add that value in next calulation.

STEP 4 :

now we will cross multiply three digits and then add the values and also add previous reminder

802

232

'8 * 2 + 0 * 3 + 2 * 2 = 20'
Result -

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if we have reminder like 2 then we will add that value in next calulation.

STEP 5 :

now we will cross multiply two digits from left and then add the values and also add previous reminder

802

232

'8 * 3 + 0 * 2 = 26'
Result -

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if we have reminder like 2 then we will add that value in next calulation.

STEP 6 :

now multiply thousends place digits and then add the values and also add previous reminder

802

232

'8 * 2 = 18'
Result -

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