HOW TO DO MULTIPLICATION OF TWO NUMBERS BY SHORT CUT MATHS TRICKS

Today we are going to learn shortest method of multiplication for two numbers which are very close to 100 ,which can save our time in competitive exams .

Let us choose two numbers   98 and  96 nearer to 100 
98×96 = (98-4)(2×4) = (94)(08) = 9408 (Only in mind )
Step 1 

Consider both the numbers as Num 1 = 98 and Num2 = 96.

Subtract Num 1 from 100 and write its Result 1 as one place .

Also Subtract Num 2 from 100 and write its as Result 2 second place .

Here Result 1 = 100 - 98 = 2
Result 2 = 100 - 96 = 4
Now multiply the results so obtained and mark it as Stepresult1. Stepresult1 = 4*2 = 8 = 08

Step 2 

Subtract the result of  Result 1 (blue Answer) from Num 2 i. e.(96 ).

Here we have
Stepresult2 = 96-2= 94

Final Answer = (Ist two digits are Stepresult2)(2nd two digits are Stepresult1)

= 9408
The result so obtained i. e. 9408 is the answer of product of two numbers

Let us do one more example in fast way

Another Example

92 * 91 = ?

Step 1

Last two digits of the answer = (100-92)(100-91)
= 8* 9 = 72

Step 2

1st two digits of the answer = (Greater number as Red highlighted in last step - Smaller number in last step Blue highlighted = 92 - 9 = 83

Final Answer = (Answer of Step 1)(Answer of Step 2) = 8372

 Example   89 * 92 = (92-11)(11*8)=8188

Let us discuss step by step the process of  multiplying these two numbers quickly

Step 1

Split Both the numbers in such a way that one the term must be 100 and other be 100-1st number. i. e. 89 will be written as 100-11 and 92 will be written as 100-8

Step 2

Now select either of the given number (suppose 92 ) and subtract the number ( other than 100 ) which is in other factor in previous step i. e. 11.

Step 3

The difference of 92-11 will the 1st two digits of our answer and product of other two digits are the 3rd and 4th digits of the answer.

One more Example

88×93 = (Answer of Step 1)(Answer of Step 2)
               =   (93-12)  [(100-88) ×(100-93)]
            = (93-12)[12×7]
             = (81)(84)
               =8184
94×84 =   (As 94 is 6 less than 100)(As 84 is 16 less than 100)
             = (subtract 16 from 94)(Multiply 6 with 16)
            = (94-16 gives 1st two digits of product) (96 will be last two digits of product)
Final answer = 7896
You can also learn it as
93 × 87 = (Greater number - How much second number closer to 100 ) ( (100-93)(100-87))

93 × 87 = (93-13)(7×13)

93×87 = 8091

Conclusion

This method was to multiply two numbers using a shortcut . Thanks for spending your precious time to read this post ,If you liked this post . Please share it with your friends and also follow me on my blog to encourage me to do better than best  for multiplication,  multiplication tricks and   
vedic maths tricks .See your in next post, till then Bye.....

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